Sublethal pesticide doses negatively affect survival and the cellular responses in American foulbrood-infected honeybee larvae

NASA Astrophysics Data System (ADS)

López, Javier Hernández; Krainer, Sophie; Engert, Antonia; Schuehly, Wolfgang; Riessberger-Gallé, Ulrike; Crailsheim, Karl

2017-02-01

Disclosing interactions between pesticides and bee infections is of most interest to understand challenges that pollinators are facing and to which extent bee health is compromised. Here, we address the individual and combined effect that three different pesticides (dimethoate, clothianidin and fluvalinate) and an American foulbrood (AFB) infection have on mortality and the cellular immune response of honeybee larvae. We demonstrate for the first time a synergistic interaction when larvae are exposed to sublethal doses of dimethoate or clothianidin in combination with Paenibacillus larvae, the causative agent of AFB. A significantly higher mortality than the expected sum of the effects of each individual stressor was observed in co-exposed larvae, which was in parallel with a drastic reduction of the total and differential hemocyte counts. Our results underline that characterizing the cellular response of larvae to individual and combined stressors allows unmasking previously undetected sublethal effects of pesticides in colony health.

Sublethal pesticide doses negatively affect survival and the cellular responses in American foulbrood-infected honeybee larvae.

PubMed

López, Javier Hernández; Krainer, Sophie; Engert, Antonia; Schuehly, Wolfgang; Riessberger-Gallé, Ulrike; Crailsheim, Karl

2017-02-01

Disclosing interactions between pesticides and bee infections is of most interest to understand challenges that pollinators are facing and to which extent bee health is compromised. Here, we address the individual and combined effect that three different pesticides (dimethoate, clothianidin and fluvalinate) and an American foulbrood (AFB) infection have on mortality and the cellular immune response of honeybee larvae. We demonstrate for the first time a synergistic interaction when larvae are exposed to sublethal doses of dimethoate or clothianidin in combination with Paenibacillus larvae, the causative agent of AFB. A significantly higher mortality than the expected sum of the effects of each individual stressor was observed in co-exposed larvae, which was in parallel with a drastic reduction of the total and differential hemocyte counts. Our results underline that characterizing the cellular response of larvae to individual and combined stressors allows unmasking previously undetected sublethal effects of pesticides in colony health.

Electromagnetic field therapy delays cellular senescence and death by enhancement of the heat shock response.

PubMed

Perez, Felipe P; Zhou, Ximing; Morisaki, Jorge; Jurivich, Donald

2008-04-01

Hormesis may result when mild repetitive stress increases cellular defense against diverse injuries. This process may also extend in vitro cellular proliferative life span as well as delay and reverse some of the age-dependent changes in both replicative and non-replicative cells. This study evaluated the potential hormetic effect of non-thermal repetitive electromagnetic field shock (REMFS) and its impact on cellular aging and mortality in primary human T lymphocytes and fibroblast cell lines. Unlike previous reports employing electromagnetic radiation, this study used a long wave length, low energy, and non-thermal REMFS (50MHz/0.5W) for various therapeutic regimens. The primary outcomes examined were age-dependent morphological changes in cells over time, cellular death prevention, and stimulation of the heat shock response. REMFS achieved several biological effects that modified the aging process. REMFS extended the total number of population doublings of mouse fibroblasts and contributed to youthful morphology of cells near their replicative lifespan. REMFS also enhanced cellular defenses of human T cells as reflected in lower cell mortality when compared to non-treated T cells. To determine the mechanism of REMFS-induced effects, analysis of the cellular heat shock response revealed Hsp90 release from the heat shock transcription factor (HSF1). Furthermore, REMFS increased HSF1 phosphorylation, enhanced HSF1-DNA binding, and improved Hsp70 expression relative to non-REMFS-treated cells. These results show that non-thermal REMFS activates an anti-aging hormetic effect as well as reduces cell mortality during lethal stress. Because the REMFS configuration employed in this study can potentially be applied to whole body therapy, prospects for translating these data into clinical interventions for Alzheimer's disease and other degenerative conditions with aging are discussed.

Effect of gangliosides in the autoimmune response induced by liposome-associated antigens.

PubMed

Correa, S G; Rivero, V E; Yranzo-Volonté, N; Romero-Piffiguer, M; Ferro, M E; Riera, C M

1993-01-01

A model of autoimmunity to rat male accessory glands (RAG) was recently developed by intraperitoneal administration of three doses of native RAG associated with liposomes. In this work we analysed the effects of gangliosides in the cellular response to RAG when they were intraperitoneally administrated prior to the second dose of liposome-associated RAG. Results show that the ganglioside treatment could modify an established DTH response. Also, gangliosides markedly reduced the number of Ia antigen-positive peritoneal exudated cells (PEC). However, they modified neither the processing of liposomes through PEC nor their viability. Moreover, we obtained cellular response by transferring PEC from immunized donors into naive receptors.

Evaluation of the health impact of nanoparticles emitted from combustion sources: Comprehensive characterization of the physicochemical properties of nanoparticle emissions from wood combustion compliances, car- and ship diesel-engines as well as investigation of their toxicological effects on human lung cells and macrophages.

NASA Astrophysics Data System (ADS)

Zimmermann, R.; Dittmar, G.; Kanashova, T.; Buters, J.; Öder, S.; Paur, H. R.; Mülhopt, S.; Dilger, M.; Weiss, C.; Harndorf, H.; Stengel, B.; Hirvonen, M. R.; Jokiniemi, J.; Hiller, K.; Sapcariu, S.; Sippula, O.; Streibel, T.; Karg, E.; Weggler, B.; Schnelle-Kreis, J.; Lintelmann, J.; Sklorz, M.; Orasche, J.; Müller, L.; Passig, J.; Gröger, T.; BéruBé, K.; Krebs, T.

2016-12-01

Combustion emissions cause health effects. The HICE-Aerosol and Health project team studies the physicochemical properties as well as biological and toxicological effects on lung cells of combustion particle emissions. The chemical composition and physical parameters thoroughly characterized. Human lung cells are exposed to the diluted combustion exhaust fumes at the air-liquid interface (ALI), allowing a realistic lung-cell exposure by simulation of the lung situation. After exposure, cellular responses of the exposed lung cells are studied by multi-omics molecular biological analyses on transcriptomic, proteomic and metabolomic level. Emissions of wood combustion (log wood, pellet heater), ship diesel engines and car gasoline engines are addressed. Special field deployable ALI-exposition systems in a mobile S2-biological laboratory were set up and applied. Human alveolar epithelial cells (A549, BEAS2B and primary cells) as well as murine macrophages were ALI-exposed to diluted emissions. The cellular effects were then comprehensively characterized (viability, cyto-toxicology, multi-omics effects monitoring) and put in context with the chemical and physical aerosol data. The following order of overall cellular response-strength was observed: A relatively mild cellular effect is observed for the diluted wood combustion emissions. Interestingly the effects-strength for log-wood and pellet burner emissions are similar, although PM-concentrations are much higher for the log-wood heater. Similar mild biological effects are observed for the gasoline car emissions. The ship diesel engine emissions induced the most intense biological responses. A surprising result in this context is, that heavy fuel oil (HFO)-emissions showed lower biological effect strengths than the supposedly cleaner diesel fuel emissions (DF). The HFO-emission contain high concentrations of known toxicants (transition metals, polycyclic aromatics). This result was recently confirmed by experiments with murine RAW macrophages. Detailed analyses of the activated cellular response pathways, such as pro-inflammatory responses, xenobiotic metabolism, phagocytosis and oxidative stress were performed. The data is suggesting a large difference in relative toxicity for different combustion sources.

Hepatic autophagy contributes to the metabolic response to dietary protein restriction.

PubMed

Henagan, Tara M; Laeger, Thomas; Navard, Alexandra M; Albarado, Diana; Noland, Robert C; Stadler, Krisztian; Elks, Carrie M; Burk, David; Morrison, Christopher D

2016-06-01

Autophagy is an essential cellular response which acts to release stored cellular substrates during nutrient restriction, and particularly plays a key role in the cellular response to amino acid restriction. However, there has been limited work testing whether the induction of autophagy is required for adaptive metabolic responses to dietary protein restriction in the whole animal. Here, we found that moderate dietary protein restriction led to a series of metabolic changes in rats, including increases in food intake and energy expenditure, the downregulation of hepatic fatty acid synthesis gene expression and reduced markers of hepatic mitochondrial number. Importantly, these effects were also associated with an induction of hepatic autophagy. To determine if the induction of autophagy contributes to these metabolic effects, we tested the metabolic response to dietary protein restriction in BCL2-AAA mice, which bear a genetic mutation that impairs autophagy induction. Interestingly, BCL2-AAA mice exhibit exaggerated responses in terms of both food intake and energy expenditure, whereas the effects of protein restriction on hepatic metabolism were significantly blunted. These data demonstrate that restriction of dietary protein is sufficient to trigger hepatic autophagy, and that disruption of autophagy significantly alters both hepatic and whole animal metabolic response to dietary protein restriction. Copyright © 2016 Elsevier Inc. All rights reserved.

RNA sequencing supports distinct reactive oxygen species-mediated pathways of apoptosis by high and low size mass fractions of Bay leaf (Lauris nobilis) in HT-29 cells.

PubMed

Rodd, Annabelle L; Ververis, Katherine; Sayakkarage, Dheeshana; Khan, Abdul W; Rafehi, Haloom; Ziemann, Mark; Loveridge, Shanon J; Lazarus, Ross; Kerr, Caroline; Lockett, Trevor; El-Osta, Assam; Karagiannis, Tom C; Bennett, Louise E

2015-08-01

Anti-proliferative and pro-apoptotic effects of Bay leaf (Laurus nobilis) in mammalian cancer and HT-29 adenocarcinoma cells have been previously attributed to effects of polyphenolic and essential oil chemical species. Recently, we demonstrated differentiated growth-regulating effects of high (HFBL) versus low molecular mass (LFBL) aqueous fractions of bay leaf and now confirm by comparative effects on gene expression, that HFBL and LFBL suppress HT-29 growth by distinct mechanisms. Induction of intra-cellular lesions including DNA strand breakage by extra-cellular HFBL, invoked the hypothesis that iron-mediated reactive oxygen species with capacity to penetrate cell membrane, were responsible for HFBL-mediated effects, supported by equivalent effects of HFBL in combination with γ radiation. Activities of HFBL and LFBL were interpreted to reflect differentiated responses to iron-mediated reactive oxygen species (ROS), occurring either outside or inside cells. In the presence of LFBL, apoptotic death was relatively delayed compared with HFBL. ROS production by LFBL mediated p53-dependent apoptosis and recovery was suppressed by promoting G1/S phase arrest and failure of cellular tight junctions. In comparison, intra-cellular anti-oxidant protection exerted by LFBL was absent for extra-cellular HFBL (likely polysaccharide-rich), which potentiated more rapid apoptosis by producing DNA double strand breaks. Differentiated effects on expression of genes regulating ROS defense and chromatic condensation by LFBL versus HFBL, were observed. The results support ferrous iron in cell culture systems and potentially in vivo, can invoke different extra-cellular versus intra-cellular ROS-mediated chemistries, that may be regulated by exogenous, including dietary species.

Cellular Interactions and Biological Responses to Titanium Dioxide Nanoparticles in HepG2 and BEAS-2B Cells: Role of Cell Culture Media

EPA Science Inventory

ABSTRACT We have shown previously that the composition of the biological medium used in vitro can affect the cellular interaction and biological response of titanium dioxide nanoparticles (nano-TiO2) in human lung epithelial cells. However, it is unclear if these effects are co...

Manipulating the antigen-specific immune response by the hydrophobicity of amphiphilic poly(γ-glutamic acid) nanoparticles.

PubMed

Shima, Fumiaki; Akagi, Takami; Uto, Tomofumi; Akashi, Mitsuru

2013-12-01

The new generation vaccines are safe but poorly immunogenic, and thus they require the use of adjuvants. However, conventional vaccine adjuvants fail to induce potent cellular immunity, and their toxicity and side-effects hinder the clinical use. Therefore, a vaccine adjuvant which is safe and can induce an antigen-specific cellular immunity-biased immune response is urgently required. In the development of nanoparticle-based vaccine adjuvants, the hydrophobicity is one of the most important factors. It could control the interaction between the encapsulated antigens and/or nanoparticles with immune cells. In this study, nanoparticles (NPs) composed of amphiphilic poly(γ-glutamic acid)-graft-L-phenylalanine ethyl ester (γ-PGA-Phe) with various grafting degrees of hydrophobic side chains were prepared to evaluate the effect of hydrophobicity of vaccine carriers on the antigen encapsulation behavior, cellular uptake, activation of dendritic cells (DCs), and induction of antigen-specific cellular immunity-biased immune responses. These NPs could efficiently encapsulate antigens, and the uptake amount of the encapsulated antigen by DCs was dependent on the hydrophobicity of γ-PGA-Phe NPs. Moreover, the activation potential of the DCs and the induction of antigen-specific cellular immunity were correlated with the hydrophobicity of γ-PGA-Phe NPs. By controlling the hydrophobicity of antigen-encapsulated γ-PGA-Phe NPs, the activation potential of DCs was able to manipulate about 5 to 30-hold than the conventional vaccine, and the cellular immunity was about 10 to 40-hold. These results suggest that the hydrophobicity of NPs is a key factor for changing the interaction between NPs and immune cells, and thus the induction of cellular immunity-biased immune response could be achieved by controlling the hydrophobicity of them. Copyright © 2013 Elsevier Ltd. All rights reserved.

Induction of strong anti-HIV cellular immunity by a combination of Clostridium perfringens expressing HIV gag and virus like particles.

PubMed

Pegu, Poonam; Helmus, Ruth; Gupta, Phalguni; Tarwater, Patrick; Caruso, Lori; Shen, Chengli; Ross, Ted; Chen, Yue

2011-12-01

The lower gastrointestinal tract is a major mucosal site of HIV entry and initial infection. Thus, the induction of strong cellular immune responses at this mucosal site will be an important feature of an effective HIV vaccine. We have used a novel prime-boost vaccination approach to induce immune responses at mucosal sites. Orally delivered recombinant Clostridium perfringens expressing HIV-1 gag (Cp-Gag) was evaluated for induction of HIV-1 Gag specific T cell responses in a prime-boost model with intranasal inoculation of HIV-1 virus like particles (VLP). HIV-1 specific cellular immune responses in both the effector (Lamina propria) and inductive sites (Peyer's patches) of the gastrointestinal (GI) tract were significantly higher in mice immunized using Cp-Gag and VLPs in a prime-boost approach compared to mice immunized with either Cp-Gag or VLPs alone. Such cellular immune response was found to be mediated by both CD8(+) and CD4(+) T cells. Such a strong mucosal immune response could be very useful in developing a mucosal vaccine against HIV-1.

Role of Complement on Broken Surfaces After Trauma.

PubMed

Huber-Lang, Markus; Ignatius, Anita; Brenner, Rolf E

2015-01-01

Activation of both the complement and coagulation cascade after trauma and subsequent local and systemic inflammatory response represent a major scientific and clinical problem. After severe tissue injury and bone fracture, exposure of innate immunity to damaged cells and molecular debris is considered a main trigger of the posttraumatic danger response. However, the effects of cellular fragments (e.g., histones) on complement activation remain enigmatic. Furthermore, direct effects of "broken" bone and cartilage surfaces on the fluid phase response of complement and its interaction with key cells of connective tissues are still unknown. Here, we summarize data suggesting direct and indirect complement activation by extracellular and cellular danger associated molecular patterns. In addition, key complement components and the corresponding receptors (such as C3aR, C5aR) have been detected on "exposed surfaces" of the damaged regions. On a cellular level, multiple effects of complement activation products on osteoblasts, osteoclasts, chondrocytes and mesenchymal stem cells have been found.In conclusion, the complement system may be activated by trauma-altered surfaces and is crucially involved in connective tissue healing and posttraumatic systemic inflammatory response.

Cellular lysis of Streptococcus faecalis induced with triton X-100.

PubMed Central

Cornett, J B; Shockman, G D

1978-01-01

Lysis of exponential-phase cultures of Streptococcus faecalis ATCC 9790 was induced by exposure to both anionic (sodium dodecyl sulfate) and nonionic (Triton X-100) surfactants. Lysis in response to sodium dodecyl sulfate was effective only over a limited range of concentrations, whereas Triton X-100-induced lysis occurred over a broad range of surfactant concentrations. The data presented indicate that the bacteriolytic response of growing cells to Triton X-100: (i) was related to the ratio of surfactant to cells and not the surfactant concentration per se; (ii) required the expression of the cellular autolytic enzyme system; and (iii) was most likely due to an effect of the surfactant on components of the autolytic system that are associated with the cytoplasmic membrane. The possibility that Triton X-100 may induce cellular lysis by releasing a lipid inhibitor of the cellular autolytic enzyme is discussed. PMID:97265

Adoptive cellular therapy of cancer: exploring innate and adaptive cellular crosstalk to improve anti-tumor efficacy.

PubMed

Payne, Kyle K; Bear, Harry D; Manjili, Masoud H

2014-08-01

The mammalian immune system has evolved to produce multi-tiered responses consisting of both innate and adaptive immune cells collaborating to elicit a functional response to a pathogen or neoplasm. Immune cells possess a shared ancestry, suggestive of a degree of coevolution that has resulted in optimal functionality as an orchestrated and highly collaborative unit. Therefore, the development of therapeutic modalities that harness the immune system should consider the crosstalk between cells of the innate and adaptive immune systems in order to elicit the most effective response. In this review, the authors will discuss the success achieved using adoptive cellular therapy in the treatment of cancer, recent trends that focus on purified T cells, T cells with genetically modified T-cell receptors and T cells modified to express chimeric antigen receptors, as well as the use of unfractionated immune cell reprogramming to achieve optimal cellular crosstalk upon infusion for adoptive cellular therapy.

Effect of Porosity of Alumina and Zirconia Ceramics toward Pre-Osteoblast Response

PubMed Central

Hadjicharalambous, Chrystalleni; Prymak, Oleg; Loza, Kateryna; Buyakov, Ales; Kulkov, Sergei; Chatzinikolaidou, Maria

2015-01-01

It is acknowledged that cellular responses are highly affected by biomaterial porosity. The investigation of this effect is important for the development of implanted biomaterials that integrate with bone tissue. Zirconia and alumina ceramics exhibit outstanding mechanical properties and are among the most popular implant materials used in orthopedics, but few data exist regarding the effect of porosity on cellular responses to these materials. The present study investigates the effect of porosity on the attachment and proliferation of pre-osteoblastic cells on zirconia and alumina. For each composition, ceramics of three different porosities are fabricated by sintering, and characterized using scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray powder diffraction. Cell proliferation is quantified, and microscopy is employed to qualitatively support the proliferation results and evaluate cell morphology. Cell adhesion and metabolic activity are found comparable among low porosity zirconia and alumina. In contrast, higher porosity favors better cell spreading on zirconia and improves growth, but does not significantly affect cell response on alumina. Between the highest porosity materials, cell response on zirconia is found superior to alumina. Results show that an average pore size of ~150 μm and ~50% porosity can be considered beneficial to cellular growth on zirconia ceramics. PMID:26579516

Cold atmospheric plasma jet-generated RONS and their selective effects on normal and carcinoma cells

PubMed Central

Kim, Sun Ja; Chung, T. H.

2016-01-01

Cold atmospheric helium plasma jets were fabricated and utilized for plasma–cell interactions. The effect of operating parameters and jet design on the generation of specific reactive oxygen and nitrogen species (RONS) within cells and cellular response were investigated. It was found that plasma treatment induced the overproduction of RONS in various cancer cell lines selectively. The plasma under a relatively low applied voltage induced the detachment of cells, a reduction in cell viability, and apoptosis, while the plasma under higher applied voltage led to cellular necrosis in our case. To determine whether plasma-induced reactive oxygen species (ROS) generation occurs through interfering with mitochondria-related cellular response, we examined the plasma effects on ROS generation in both parental A549 cells and A549 ρ0 cells. It was observed that cancer cells were more susceptible to plasma-induced RONS (especially nitric oxide (NO) and nitrogen dioxide (NO2−) radicals) than normal cells, and consequently, plasma induced apoptotic cell responses mainly in cancer cells. PMID:26838306

Heat shock cognate 71 (HSC71) regulates cellular antiviral response by impairing formation of VISA aggregates.

PubMed

Liu, Zhigang; Wu, Shu-Wen; Lei, Cao-Qi; Zhou, Qian; Li, Shu; Shu, Hong-Bing; Wang, Yan-Yi

2013-05-01

In response to viral infection, RIG-I-like RNA helicases detect viral RNA and signal through the mitochondrial adapter protein VISA. VISA activation leads to rapid activation of transcription factors IRF3 and NF-κB, which collaborate to induce transcription of type I interferon (IFN) genes and cellular antiviral response. It has been demonstrated that VISA is activated by forming prion-like aggregates. However, how this process is regulated remains unknown. Here we show that overexpression of HSC71 resulted in potent inhibition of virus-triggered transcription of IFNB1 gene and cellular antiviral response. Consistently, knockdown of HSC71 had opposite effects. HSC71 interacted with VISA, and negatively regulated virus-triggered VISA aggregation. These findings suggest that HSC71 functions as a check against VISA-mediated antiviral response.

Toxicity potentials from waste cellular phones, and a waste management policy integrating consumer, corporate, and government responsibilities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lim, Seong-Rin; Schoenung, Julie M., E-mail: jmschoenung@ucdavis.ed

Cellular phones have high environmental impact potentials because of their heavy metal content and current consumer attitudes toward purchasing new phones with higher functionality and neglecting to return waste phones into proper take-back systems. This study evaluates human health and ecological toxicity potentials from waste cellular phones; highlights consumer, corporate, and government responsibilities for effective waste management; and identifies key elements needed for an effective waste management strategy. The toxicity potentials are evaluated by using heavy metal content, respective characterization factors, and a pathway and impact model for heavy metals that considers end-of-life disposal in landfills or by incineration. Cancermore » potentials derive primarily from Pb and As; non-cancer potentials primarily from Cu and Pb; and ecotoxicity potentials primarily from Cu and Hg. These results are not completely in agreement with previous work in which leachability thresholds were the metric used to establish priority, thereby indicating the need for multiple or revised metrics. The triple bottom line of consumer, corporate, and government responsibilities is emphasized in terms of consumer attitudes, design for environment (DfE), and establishment and implementation of waste management systems including recycling streams, respectively. The key strategic elements for effective waste management include environmental taxation and a deposit-refund system to motivate consumer responsibility, which is linked and integrated with corporate and government responsibilities. The results of this study can contribute to DfE and waste management policy for cellular phones.« less

Toxicity potentials from waste cellular phones, and a waste management policy integrating consumer, corporate, and government responsibilities.

PubMed

Lim, Seong-Rin; Schoenung, Julie M

2010-01-01

Cellular phones have high environmental impact potentials because of their heavy metal content and current consumer attitudes toward purchasing new phones with higher functionality and neglecting to return waste phones into proper take-back systems. This study evaluates human health and ecological toxicity potentials from waste cellular phones; highlights consumer, corporate, and government responsibilities for effective waste management; and identifies key elements needed for an effective waste management strategy. The toxicity potentials are evaluated by using heavy metal content, respective characterization factors, and a pathway and impact model for heavy metals that considers end-of-life disposal in landfills or by incineration. Cancer potentials derive primarily from Pb and As; non-cancer potentials primarily from Cu and Pb; and ecotoxicity potentials primarily from Cu and Hg. These results are not completely in agreement with previous work in which leachability thresholds were the metric used to establish priority, thereby indicating the need for multiple or revised metrics. The triple bottom line of consumer, corporate, and government responsibilities is emphasized in terms of consumer attitudes, design for environment (DfE), and establishment and implementation of waste management systems including recycling streams, respectively. The key strategic elements for effective waste management include environmental taxation and a deposit-refund system to motivate consumer responsibility, which is linked and integrated with corporate and government responsibilities. The results of this study can contribute to DfE and waste management policy for cellular phones. 2010 Elsevier Ltd. All rights reserved.

Mechanisms of information decoding in a cascade system of gene expression

NASA Astrophysics Data System (ADS)

Wang, Haohua; Yuan, Zhanjiang; Liu, Peijiang; Zhou, Tianshou

2016-05-01

Biotechnology advances have allowed investigation of heterogeneity of cellular responses to stimuli on the single-cell level. Functionally, this heterogeneity can compromise cellular responses to environmental signals, and it can also enlarge the repertoire of possible cellular responses and hence increase the adaptive nature of cellular behaviors. However, the mechanism of how this response heterogeneity is generated remains elusive. Here, by systematically analyzing a representative cellular signaling system, we show that (1) the upstream activator always amplifies the downstream burst frequency (BF) but the noiseless activator performs better than the noisy one, remarkably for small or moderate input signal strengths, and the repressor always reduces the downstream BF but the difference in the reducing effect between noiseless and noise repressors is very small; (2) both the downstream burst size and mRNA mean are a monotonically increasing function of the activator strength but a monotonically decreasing function of the repressor strength; (3) for repressor-type input, there is a noisy signal strength such that the downstream mRNA noise arrives at an optimal level, but for activator-type input, the output noise intensity is fundamentally a monotonically decreasing function of the input strength. Our results reveal the essential mechanisms of both signal information decoding and cellular response heterogeneity, whereas our analysis provides a paradigm for analyzing dynamics of noisy biochemical signaling systems.

NF-kB activation and its downstream target genes expression after heavy ions exposure

NASA Astrophysics Data System (ADS)

Chishti, Arif Ali; Baumstark-Khan, Christa; Hellweg, Christine; Schmitz, Claudia; Koch, Kristina; Feles, Sebastian

2016-07-01

To enable long-term human space flight cellular radiation response to densely ionizing radiation needs to be better understood for developing appropriate countermeasures to mitigate acute effects and late radiation risks for the astronaut. The biological effectiveness of accelerated heavy ions (which constitute the most important radiation type in space) with high linear energy transfer (LET) for effecting DNA damage response pathways as a gateway to cell death or survival is of major concern not only for space missions but also for new regimes of tumor radiotherapy. In the current research study, the contribution of NF-κB in response to space-relevant radiation qualities was determined by a NF-κB reporter cell line (HEK-pNF-κB-d2EGFP/Neo L2). The NF-κB dependent reporter gene expression (d2EGFP) after ionizing radiation (X-rays and heavy ions) exposure was evaluated by flow cytometry. Because of differences in the extent of NF-κB activation after X-irradiation and heavy ions exposure, it was expected that radiation quality (LET) might play an important role in the cellular radiation response. In addition, the biological effectiveness (RBE) of NF-κB activation and reduction of cellular survival was examined for heavy ions having a broad range of LET (˜0.3 - 9674 keV/µm). Furthermore, the effect of LET on NF-κB target gene expression was analyzed by real time reverse transcriptase quantitative PCR (RT-qPCR). In this study it was proven that NF-κB activation and NF-κB dependent gene expression comprises an early step in cellular radiation response. Taken together, this study clearly demonstrates that NF-κB activation and NF-κB-dependent gene expression by heavy ions are highest in the LET range of ˜50-200 keV/μupm. The up-regulated chemokines and cytokines (CXCL1, CXCL2, CXCL10, IL-8 and TNF) might be important for cell-cell communication among hit as well as unhit cells (bystander effect). The results obtained suggest the NF-κB pathway to be a promising target for pharmacological modulation of cellular radiation response either to improve tumor cell killing during radiotherapy with heavy ions or to mitigate radiation late effects in astronauts or irradiated healthy tissue.

Norovirus P particle efficiently elicits innate, humoral and cellular immunity.

PubMed

Fang, Hao; Tan, Ming; Xia, Ming; Wang, Leyi; Jiang, Xi

2013-01-01

Norovirus (NoV) P domain complexes, the 24 mer P particles and the P dimers, induced effective humoral immunity, but their role in the cellular immune responses remained unclear. We reported here a study on cellular immune responses of the two P domain complexes in comparison with the virus-like particle (VLP) of a GII.4 NoV (VA387) in mice. The P domain complexes induced significant central memory CD4(+) T cell phenotypes (CD4(+) CD44(+) CD62L(+) CCR7(+)) and activated polyclonal CD4(+) T cells as shown by production of Interleukin (IL)-2, Interferon (IFN)-γ, and Tumor Necrosis Factor (TNF)-α. Most importantly, VA387-specific CD4(+) T cell epitope induced a production of IFN-γ, indicating an antigen-specific CD4(+) T cell response in P domain complex-immunized mice. Furthermore, P domain complexes efficiently induced bone marrow-derived dendritic cell (BMDC) maturation, evidenced by up-regulation of co-stimulatory and MHC class II molecules, as well as production of IL-12 and IL-1β. Finally, P domain complex-induced mature dendritic cells (DCs) elicited proliferation of specific CD4(+) T cells targeting VA387 P domain. Overall, we conclude that the NoV P domain complexes are efficiently presented by DCs to elicit not only humoral but also cellular immune responses against NoVs. Since the P particle is highly effective for both humoral and cellular immune responses and easily produced in Escherichia coli (E. coli), it is a good choice of vaccine against NoVs and a vaccine platform against other diseases.

Dynamics of Cellular Responses to Radiation

PubMed Central

Wodarz, Dominik; Sorace, Ron; Komarova, Natalia L.

2014-01-01

Understanding the consequences of exposure to low dose ionizing radiation is an important public health concern. While the risk of low dose radiation has been estimated by extrapolation from data at higher doses according to the linear non-threshold model, it has become clear that cellular responses can be very different at low compared to high radiation doses. Important phenomena in this respect include radioadaptive responses as well as low-dose hyper-radiosensitivity (HRS) and increased radioresistance (IRR). With radioadaptive responses, low dose exposure can protect against subsequent challenges, and two mechanisms have been suggested: an intracellular mechanism, inducing cellular changes as a result of the priming radiation, and induction of a protected state by inter-cellular communication. We use mathematical models to examine the effect of these mechanisms on cellular responses to low dose radiation. We find that the intracellular mechanism can account for the occurrence of radioadaptive responses. Interestingly, the same mechanism can also explain the existence of the HRS and IRR phenomena, and successfully describe experimentally observed dose-response relationships for a variety of cell types. This indicates that different, seemingly unrelated, low dose phenomena might be connected and driven by common core processes. With respect to the inter-cellular communication mechanism, we find that it can also account for the occurrence of radioadaptive responses, indicating redundancy in this respect. The model, however, also suggests that the communication mechanism can be vital for the long term survival of cell populations that are continuously exposed to relatively low levels of radiation, which cannot be achieved with the intracellular mechanism in our model. Experimental tests to address our model predictions are proposed. PMID:24722167

Modulation of Cellular Stress Response via the Erythropoietin/CD131 Heteroreceptor Complex in Mouse Mesenchymal-Derived Cells

PubMed Central

Bohr, Stefan; Patel, Suraj J; Vasko, Radovan; Shen, Keyue; Iracheta-Vellve, Arvin; Lee, Jungwoo; Bale, Shyam Sundhar; Chakraborty, Nilay; Brines, Michael; Cerami, Anthony; Berthiaume, Francois; Yarmush, Martin L

2014-01-01

Tissue protective properties of erythropoietin (EPO) have let to the discovery of an alternative EPO-signaling via an EPO-R/CD131 receptor complex which can now be specifically targeted through pharmaceutically designed short sequence peptides such as ARA290. However, little is still known about specific functions of alternative EPO-signaling in defined cell populations. In this study we investigated effects of signaling through EPO-R/CD131 complex on cellular stress responses and pro-inflammatory activation in different mesenchymal-derived phenotypes. We show that anti-apoptotic, anti-inflammatory effects of ARA290 and EPO coincide with the externalization of CD131 receptor component as an immediate response to cellular stress. In addition, alternative EPO-signaling strongly modulated transcriptional, translational or metabolic responses after stressor removal. Specifically, we saw that ARA290 was able overcome a TNFα-mediated inhibition of transcription factor activation related to cell stress responses, most notably of serum response factor (SRF), heat shock transcription factor protein 1 (HSF1) and activator protein 1 (AP1). We conclude that alternative EPO-signaling acts as a modulator of pro-inflammatory signaling pathways and likely plays a role in restoring tissue homeostasis. PMID:25373867

Cellular evaluation of the toxicity of combustion derived particulate matter: influence of particle grinding and washing on cellular response.

PubMed

Katterman, Matthew E; Birchard, Stephanie; Seraphin, Supapan; Riley, Mark R

2007-01-01

There is increasing interest in continual monitoring of air for the presence of inhalation health hazards, such as particulate matter, produced through combustion of fossil fuels. Currently there are no means to rapidly evaluate the relative toxicity of materials or to reliably predict potential health impact due to the complexity of the composition, size, and physical properties of particulate matter. This research evaluates the feasibility of utilizing cell cultures as the biological recognition element of an inhalation health monitoring system. The response of rat lung type II epithelial (RLE-6TN) cells to a variety of combustion derived particulates and their components has been evaluated. The focus of the current work is an evaluation of how particles are delivered to a cellular sensing array and to what degree does washing or grinding of the particles impacts the cellular response. There were significant differences in the response of these lung cells to PM's of varying sources. Mechanical grinding or washing was found to alter the toxicity of some of these particulates; however these effects were strongly dependent on the fuel source. Washing reduced toxicity of oil PM's, but had little effect on those from diesel or coal. Mechanical grinding could significantly increase the toxicity of coal PM's, but not for oil or diesel.

Effects of ozone on the defense to a respiratory Listeria monocytogenes infection in the rat. Suppression of macrophage function and cellular immunity and aggravation of histopathology in lung and liver during infection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Van Loveren, H.; Rombout, P.J.; Wagenaar, S.S.

1988-07-01

We have investigated the effect of exposure to ozone on defense mechanisms to a respiratory infection with Listeria monocytogenes in the rat. For this purpose rats were continuously exposed to O/sub 3/ concentrations ranging from 0.25 to 2.0 mg/m3 for a period of 1 week. In this model defense to a respiratory infection with Listeria depends on acquired specific cellular immune responses, as well as on natural nonspecific defense mechanisms. The results confirm earlier findings that show that ozone exposure can suppress the capacity of macrophages to ingest and kill Listeria. Moreover, the results show that ozone can also havemore » a suppressive effect on the development of cellular immune responses to a respiratory Listeria infection, i.e., on T/B ratios in lung draining lymph nodes, delayed-type hypersensitivity responses to Listeria antigen, and lymphoproliferative responses in spleen and lung draining lymph nodes to Listeria antigen. The effects on the specific immune responses are especially overt if exposure to the oxidant gas occurs during an ongoing primary infection. The pathological lesions induced by a pulmonary Listeria monocytogenes infection were characterized by multifocal infiltrates of histiocytic and lymphoid cells. The foci sometimes had a granulomatous appearance. Moreover, the cellularity of the interstitial tissues was increased. In the lung many diffuse alveolar macrophages could be seen in the alveoli. Ozone exposure greatly increased the severity of the lung lesions and also of liver lesions resulting from the pulmonary infection. A prominent finding was the formation of granulomas in ozone-exposed and Listeria-infected rats.« less

Cellular response of preosteoblasts to nanograined/ultrafine-grained structures.

PubMed

Misra, R D K; Thein-Han, W W; Pesacreta, T C; Hasenstein, K H; Somani, M C; Karjalainen, L P

2009-06-01

Metallic materials with submicron- to nanometer-sized grains provide surfaces that are different from conventional polycrystalline materials because of the large proportion of grain boundaries with high free energy. In the study described here, the combination of cellular and molecular biology, materials science and engineering advances our understanding of cell-substrate interactions, especially the cellular activity between preosteoblasts and nanostructured metallic surfaces. Experiments on the effect of nano-/ultrafine grains have shown that cell attachment, proliferation, viability, morphology and spread are favorably modulated and significantly different from conventional coarse-grained structures. Additionally, immunofluorescence studies demonstrated stronger vinculin signals associated with actin stress fibers in the outer regions of the cells and cellular extensions on nanograined/ultrafine-grained substrate. These observations suggest enhanced cell-substrate interaction and activity. The differences in the cellular response on nanograined/ultrafine-grained and coarse-grained substrates are attributed to grain size and degree of hydrophilicity. The outcomes of the study are expected to reduce challenges to engineer bulk nanostructured materials with specific physical and surface properties for medical devices with improved cellular attachment and response. The data lay the foundation for a new branch of nanostructured materials for biomedical applications.

Mechanisms and biological importance of photon-induced bystander responses: do they have an impact on low-dose radiation responses

PubMed Central

Tomita, Masanori; Maeda, Munetoshi

2015-01-01

Abstract Elucidating the biological effect of low linear energy transfer (LET), low-dose and/or low-dose-rate ionizing radiation is essential in ensuring radiation safety. Over the past two decades, non-targeted effects, which are not only a direct consequence of radiation-induced initial lesions produced in cellular DNA but also of intra- and inter-cellular communications involving both targeted and non-targeted cells, have been reported and are currently defining a new paradigm in radiation biology. These effects include radiation-induced adaptive response, low-dose hypersensitivity, genomic instability, and radiation-induced bystander response (RIBR). RIBR is generally defined as a cellular response that is induced in non-irradiated cells that receive bystander signals from directly irradiated cells. RIBR could thus play an important biological role in low-dose irradiation conditions. However, this suggestion was mainly based on findings obtained using high-LET charged-particle radiations. The human population (especially the Japanese, who are exposed to lower doses of radon than the world average) is more frequently exposed to low-LET photons (X-rays or γ-rays) than to high-LET charged-particle radiation on a daily basis. There are currently a growing number of reports describing a distinguishing feature between photon-induced bystander response and high-LET RIBR. In particular, photon-induced bystander response is strongly influenced by irradiation dose, the irradiated region of the targeted cells, and p53 status. The present review focuses on the photon-induced bystander response, and discusses its impact on the low-dose radiation effect. PMID:25361549

Differential cellular responses by oncogenic levels of c-Myc expression in long-term confluent retinal pigment epithelial cells.

PubMed

Wang, Yiping; Cheng, Xiangdong; Samma, Muhammad Kaleem; Kung, Sam K P; Lee, Clement M; Chiu, Sung Kay

2018-06-01

c-Myc is a highly pleiotropic transcription factor known to control cell cycle progression, apoptosis, and cellular transformation. Normally, ectopic expression of c-Myc is associated with promoting cell proliferation or triggering cell death via activating p53. However, it is not clear how the levels of c-Myc lead to different cellular responses. Here, we generated a series of stable RPE cell clones expressing c-Myc at different levels, and found that consistent low level of c-Myc induced cellular senescence by activating AP4 in post-confluent RPE cells, while the cells underwent cell death at high level of c-Myc. In addition, high level of c-Myc could override the effect of AP4 on cellular senescence. Further knockdown of AP4 abrogated senescence-like phenotype in cells expressing low level of c-Myc, and accelerated cell death in cells with medium level of c-Myc, indicating that AP4 was required for cellular senescence induced by low level of c-Myc.

Dynamic interactions between 14-3-3 proteins and phosphoproteins regulate diverse cellular processes

PubMed Central

2004-01-01

14-3-3 proteins exert an extraordinarily widespread influence on cellular processes in all eukaryotes. They operate by binding to specific phosphorylated sites on diverse target proteins, thereby forcing conformational changes or influencing interactions between their targets and other molecules. In these ways, 14-3-3s ‘finish the job’ when phosphorylation alone lacks the power to drive changes in the activities of intracellular proteins. By interacting dynamically with phosphorylated proteins, 14-3-3s often trigger events that promote cell survival – in situations from preventing metabolic imbalances caused by sudden darkness in leaves to mammalian cell-survival responses to growth factors. Recent work linking specific 14-3-3 isoforms to genetic disorders and cancers, and the cellular effects of 14-3-3 agonists and antagonists, indicate that the cellular complement of 14-3-3 proteins may integrate the specificity and strength of signalling through to different cellular responses. PMID:15167810

A multi-physics model for ultrasonically activated soft tissue.

PubMed

Suvranu De, Rahul

2017-02-01

A multi-physics model has been developed to investigate the effects of cellular level mechanisms on the thermomechanical response of ultrasonically activated soft tissue. Cellular level cavitation effects have been incorporated in the tissue level continuum model to accurately determine the thermodynamic states such as temperature and pressure. A viscoelastic material model is assumed for the macromechanical response of the tissue. The cavitation model based equation-of-state provides the additional pressure arising from evaporation of intracellular and cellular water by absorbing heat due to structural and viscoelastic heating in the tissue, and temperature to the continuum level thermomechanical model. The thermomechanical response of soft tissue is studied for the operational range of frequencies of oscillations and applied loads for typical ultrasonically activated surgical instruments. The model is shown to capture characteristics of ultrasonically activated soft tissue deformation and temperature evolution. At the cellular level, evaporation of water below the boiling temperature under ambient conditions is indicative of protein denaturation around the temperature threshold for coagulation of tissues. Further, with increasing operating frequency (or loading), the temperature rises faster leading to rapid evaporation of tissue cavity water, which may lead to accelerated protein denaturation and coagulation.

Over-Expression of Superoxide Dismutase Ameliorates Cr(VI) Induced Adverse Effects via Modulating Cellular Immune System of Drosophila melanogaster

PubMed Central

Pragya, Prakash; Shukla, Arvind Kumar; Murthy, Ramesh Chandra; Abdin, Malik Zainul; Kar Chowdhuri, Debapratim

2014-01-01

The evolutionarily conserved innate immune system plays critical role for maintaining the health of an organism. However, a number of environmental chemicals including metals are known to exert adverse effects on immune system. The present study assessed the in vivo effect of a major environmental chemical, Cr(VI), on cellular immune response using Drosophila melanogaster and subsequently the protective role of superoxide dismutase (SOD) based on the comparable performance of the tested anti-oxidant enzymes. The immuno-modulatory potential of Cr(VI) was demonstrated by observing a significant reduction in the total hemocyte count along with impaired phagocytic activity in exposed organism. Concurrently, a significant increase in the percentage of Annexin V-FITC positive cells, activation of DEVDase activity, generation of free radical species along with inhibition of anti-oxidant enzyme activities was observed in the hemocytes of exposed organism. In addition, we have shown that ONOO− is primarily responsible for Cr(VI) induced adverse effects on Drosophila hemocytes along with O2 −. While generation of O2 −/ONOO− in Cr(VI) exposed Drosophila hemocytes was found to be responsible for the suppression of Drosophila cellular immune response, Cr(VI) induced alteration was significantly reduced by the over-expression of sod in Drosophila hemocytes. Overall, our results suggest that manipulation of one of the anti-oxidant genes, sod, benefits the organism from Cr(VI) induced alteration in cellular immunity. Further, this study demonstrates the applicability of D. melanogaster to examine the possible effects of environmental chemicals on innate immunity which can be extrapolated to higher organisms due to evolutionary conservation of innate immune system between Drosophila and mammals. PMID:24505420

Inflammatory responses to secondary organic aerosols (SOA) generated from biogenic and anthropogenic precursors

NASA Astrophysics Data System (ADS)

Tuet, Wing Y.; Chen, Yunle; Fok, Shierly; Champion, Julie A.; Ng, Nga L.

2017-09-01

Cardiopulmonary health implications resulting from exposure to secondary organic aerosols (SOA), which comprise a significant fraction of ambient particulate matter (PM), have received increasing interest in recent years. In this study, alveolar macrophages were exposed to SOA generated from the photooxidation of biogenic and anthropogenic precursors (isoprene, α-pinene, β-caryophyllene, pentadecane, m-xylene, and naphthalene) under different formation conditions (RO2 + HO2 vs. RO2 + NO dominant, dry vs. humid). Various cellular responses were measured, including reactive oxygen and nitrogen species (ROS/RNS) production and secreted levels of cytokines, tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). SOA precursor identity and formation condition affected all measured responses in a hydrocarbon-specific manner. With the exception of naphthalene SOA, cellular responses followed a trend where TNF-α levels reached a plateau with increasing IL-6 levels. ROS/RNS levels were consistent with relative levels of TNF-α and IL-6, due to their respective inflammatory and anti-inflammatory effects. Exposure to naphthalene SOA, whose aromatic-ring-containing products may trigger different cellular pathways, induced higher levels of TNF-α and ROS/RNS than suggested by the trend. Distinct cellular response patterns were identified for hydrocarbons whose photooxidation products shared similar chemical functionalities and structures, which suggests that the chemical structure (carbon chain length and functionalities) of photooxidation products may be important for determining cellular effects. A positive nonlinear correlation was also detected between ROS/RNS levels and previously measured DTT (dithiothreitol) activities for SOA samples. In the context of ambient samples collected during summer and winter in the greater Atlanta area, all laboratory-generated SOA produced similar or higher levels of ROS/RNS and DTT activities. These results suggest that the health effects of SOA are important considerations for understanding the health implications of ambient aerosols.

Toxicity evaluation of e-juice and its soluble aerosols generated by electronic cigarettes using recombinant bioluminescent bacteria responsive to specific cellular damages.

PubMed

Bharadwaj, Shiv; Mitchell, Robert J; Qureshi, Anjum; Niazi, Javed H

2017-04-15

Electronic-cigarettes (e-cigarette) are widely used as an alternative to traditional cigarettes but their safety is not well established. Herein, we demonstrate and validate an analytical method to discriminate the deleterious effects of e-cigarette refills (e-juice) and soluble e-juice aerosol (SEA) by employing stress-specific bioluminescent recombinant bacterial cells (RBCs) as whole-cell biosensors. These RBCs carry luxCDABE-operon tightly controlled by promoters that specifically induced to DNA damage (recA), superoxide radicals (sodA), heavy metals (copA) and membrane damage (oprF). The responses of the RBCs following exposure to various concentrations of e-juice/SEA was recorded in real-time that showed dose-dependent stress specific-responses against both the e-juice and vaporized e-juice aerosols produced by the e-cigarette. We also established that high doses of e-juice (4-folds diluted) lead to cell death by repressing the cellular machinery responsible for repairing DNA-damage, superoxide toxicity, ion homeostasis and membrane damage. SEA also caused the cellular damages but the cells showed enhanced bioluminescence expression without significant growth inhibition, indicating that the cells activated their global defense system to repair these damages. DNA fragmentation assay also revealed the disintegration of total cellular DNA at sub-toxic doses of e-juice. Despite their state of matter, the e-juice and its aerosols induce cytotoxicity and alter normal cellular functions, respectively that raises concerns on use of e-cigarettes as alternative to traditional cigarette. The ability of RBCs in detecting both harmful effects and toxicity mechanisms provided a fundamental understanding of biological response to e-juice and aerosols. Copyright © 2016 Elsevier B.V. All rights reserved.

Organochlorine pesticide, endosulfan induced cellular and organismal response in Drosophila melanogaster.

PubMed

Sharma, Anurag; Mishra, M; Shukla, A K; Kumar, R; Abdin, M Z; Chowdhuri, D Kar

2012-06-30

The effect of endosulfan (0.02-2.0μgmL(-1)) to Drosophila melanogaster (Oregon R(+)) at the cellular and organismal levels was examined. Third instar larvae of D. melanogaster and the strains transgenic for hsp70, hsp83 and hsp26 were exposed to endosulfan through food for 12-48h to examine the heat shock proteins (hsps), reactive oxygen species (ROS) generation, anti-oxidant stress markers and xenobiotic metabolism enzymes. We observed a concentration- and time-dependent significant induction of only small hsps (hsp23>hsp22) in the exposed organism in concurrence with a significant induction of ROS generation, oxidative stress and xenobiotic metabolism markers. Sub-organismal response was to be propagated towards organismal response, i.e., delay in the emergence of flies and decreased locomotor behaviour. Organisms with diminished locomotion also exhibited significantly lowered acetylcholinesterase activity. A significant positive correlation observed among ROS generation and different cellular endpoints (small hsps, oxidative stress markers, cytochrome P450 activities) in the exposed organism indicate a modulatory role of ROS in endosulfan-mediated cellular toxicity. The study thus suggests that the adverse effects of endosulfan in exposed Drosophila are manifested both at cellular and organismal levels and recommends Drosophila as an alternative animal model for screening the risk caused by environmental chemicals. Copyright © 2012 Elsevier B.V. All rights reserved.

EFFECT OF X-IRRADIATION ON THE CELLULAR AND HUMORAL RESPONSES TO ANTIGEN

DOE Office of Scientific and Technical Information (OSTI.GOV)

Speirs, R.S.

1962-01-01

Mice were immunized by 6 subcutaneous injections of tetanus toxoid before exposure to 500 r x radiation. At various times after irradiation the animals were challenged with intraperitoneal injections of tetanus toxoid and serum antibody titers were determined. Results indicate that the time of irradiation in relation to antigen injection greatly influences the cellular response as well as antibody production. High radiation doses prior to antigen injection reduce the number of cells capable of responding and also inhibit the production of antibody. As the animals recovered from the effects of irradiation the production of antibody appeared to reflect the capacitymore » of the eosinophils to respond. It was concluded that eosinophils play an intermediate role in the cellular everts that lead to the production of antibody. (C.H.)« less

Analysis of lead toxicity in human cells.

PubMed

Gillis, Bruce S; Arbieva, Zarema; Gavin, Igor M

2012-07-27

Lead is a metal with many recognized adverse health side effects, and yet the molecular processes underlying lead toxicity are still poorly understood. Quantifying the injurious effects of lead is also difficult because of the diagnostic limitations that exist when analyzing human blood and urine specimens for lead toxicity. We analyzed the deleterious impact of lead on human cells by measuring its effects on cytokine production and gene expression in peripheral blood mononuclear cells. Lead activates the secretion of the chemokine IL-8 and impacts mitogen-dependent activation by increasing the secretion of the proinflammatory cytokines IL-6 and TNF-α and of the chemokines IL-8 and MIP1-α in the presence of phytohemagglutinin. The recorded changes in gene expression affected major cellular functions, including metallothionein expression, and the expression of cellular metabolic enzymes and protein kinase activity. The expression of 31 genes remained elevated after the removal of lead from the testing medium thereby allowing for the measurement of adverse health effects of lead poisoning. These included thirteen metallothionein transcripts, three endothelial receptor B transcripts and a number of transcripts which encode cellular metabolic enzymes. Cellular responses to lead correlated with blood lead levels and were significantly altered in individuals with higher lead content resultantly affecting the nervous system, the negative regulation of transcription and the induction of apoptosis. In addition, we identified changes in gene expression in individuals with elevated zinc protoporphyrin blood levels and found that genes regulating the transmission of nerve impulses were affected in these individuals. The affected pathways were G-protein mediated signaling, gap junction signaling, synaptic long-term potentiation, neuropathic pain signaling as well as CREB signaling in neurons. Cellular responses to lead were altered in subjects with high zinc protoporphyrin blood levels. The results of our study defined specific changes in gene and protein expression in response to lead challenges and determined the injurious effects of exposures to lead on a cellular level. This information can be used for documenting the health effects of exposures to lead which will facilitate identifying and monitoring efficacious treatments for lead-related maladies.

Analysis of lead toxicity in human cells

PubMed Central

2012-01-01

Background Lead is a metal with many recognized adverse health side effects, and yet the molecular processes underlying lead toxicity are still poorly understood. Quantifying the injurious effects of lead is also difficult because of the diagnostic limitations that exist when analyzing human blood and urine specimens for lead toxicity. Results We analyzed the deleterious impact of lead on human cells by measuring its effects on cytokine production and gene expression in peripheral blood mononuclear cells. Lead activates the secretion of the chemokine IL-8 and impacts mitogen-dependent activation by increasing the secretion of the proinflammatory cytokines IL-6 and TNF-α and of the chemokines IL-8 and MIP1-α in the presence of phytohemagglutinin. The recorded changes in gene expression affected major cellular functions, including metallothionein expression, and the expression of cellular metabolic enzymes and protein kinase activity. The expression of 31 genes remained elevated after the removal of lead from the testing medium thereby allowing for the measurement of adverse health effects of lead poisoning. These included thirteen metallothionein transcripts, three endothelial receptor B transcripts and a number of transcripts which encode cellular metabolic enzymes. Cellular responses to lead correlated with blood lead levels and were significantly altered in individuals with higher lead content resultantly affecting the nervous system, the negative regulation of transcription and the induction of apoptosis. In addition, we identified changes in gene expression in individuals with elevated zinc protoporphyrin blood levels and found that genes regulating the transmission of nerve impulses were affected in these individuals. The affected pathways were G-protein mediated signaling, gap junction signaling, synaptic long-term potentiation, neuropathic pain signaling as well as CREB signaling in neurons. Cellular responses to lead were altered in subjects with high zinc protoporphyrin blood levels. Conclusions The results of our study defined specific changes in gene and protein expression in response to lead challenges and determined the injurious effects of exposures to lead on a cellular level. This information can be used for documenting the health effects of exposures to lead which will facilitate identifying and monitoring efficacious treatments for lead-related maladies. PMID:22839698

TLR7 imidazoquinoline ligand 3M-019 is a potent adjuvant for pure protein prototype vaccines.

PubMed

Johnston, Dean; Zaidi, Bushra; Bystryn, Jean-Claude

2007-08-01

Cancer vaccines, while theoretically attractive, present difficult challenges that must be overcome to be effective. Cancer vaccines are often poorly immunogenic and may require augmentation of immunogenicity through the use of adjuvants and/or immune response modifiers. Toll-like receptor (TLR) ligands are a relatively new class of immune response modifiers that may have great potential in inducing and augmenting both cellular and humoral immunity to vaccines. TLR7 ligands produce strong cellular responses and specific IgG2a and IgG2b antibody responses to protein immunogens. This study shows that a new TLR7 ligand, 3M-019, in combination with liposomes produces very strong immune responses to a pure protein prototype vaccine in mice. Female C57BL/6 mice were immunized subcutaneously with ovalbumin (OVA, 0.1 mg/dose) weekly 4x. Some groups were immunized to OVA plus 3M-019 or to OVA plus 3M-019 encapsulated in liposomes. Both antibody and cellular immune responses against OVA were measured after either two or four immunizations. Anti-OVA IgG antibody responses were significantly increased after two immunizations and were substantially higher after four immunizations in mice immunized with OVA combined with 3M-019. Encapsulation in liposomes further augmented antibody responses. IgM responses, on the other hand, were lowered by 3M-019. OVA-specific IgG2a levels were increased 625-fold by 3M-019 in liposomes compared to OVA alone, while anti-OVA IgG2b levels were over 3,000 times higher. In both cases encapsulation of 3M-019 in liposomes was stronger than either liposomes alone or 3M-019 without liposomes. Cellular immune responses were likewise increased by 3M-019 but further enhanced when it was encapsulated in liposomes. The lack of toxicity also indicates that this combination may by safe, effective method to boost immune response to cancer vaccines.

The Immunology of Posttransplant CMV Infection: Potential Effect of CMV Immunoglobulins on Distinct Components of the Immune Response to CMV

PubMed Central

Carbone, Javier

2016-01-01

Abstract The immune response to cytomegalovirus (CMV) infection is highly complex, including humoral, cellular, innate, and adaptive immune responses. Detection of CMV by the innate immune system triggers production of type I IFNs and inflammatory cytokines which initiate cellular and humoral responses that are critical during the early viremic phase of CMV infection. Sustained control of CMV infection is largely accounted for by cellular immunity, involving various T-cell and B-cell subsets. In solid organ transplant patients, global suppression of innate and adaptive immunities by immunosuppressive agents limits immunological defense, including inhibition of natural killer cell activity with ongoing lowering of Ig levels and CMV-specific antibody titers. This is coupled with a short-term suppression of CMV-specific T cells, the extent and duration of which can predict risk of progression to CMV viremia. CMV immunoglobulin (CMVIG) preparations have the potential to exert immunomodulatory effects as well as providing passive immunization. Specific CMVIG antibodies and virus neutralization might be enhanced by modulation of dendritic cell activity and by a decrease in T-cell activation, effects which are of importance during the initial phase of infection. In summary, the role of CMVIG in reconstituting specific anti-CMV antibodies may be enhanced by some degree of modulation of the innate and adaptive immune responses, which could help to control some of the direct and indirect effects of CMV infection. PMID:26900990

The Immunology of Posttransplant CMV Infection: Potential Effect of CMV Immunoglobulins on Distinct Components of the Immune Response to CMV.

PubMed

Carbone, Javier

2016-03-01

The immune response to cytomegalovirus (CMV) infection is highly complex, including humoral, cellular, innate, and adaptive immune responses. Detection of CMV by the innate immune system triggers production of type I IFNs and inflammatory cytokines which initiate cellular and humoral responses that are critical during the early viremic phase of CMV infection. Sustained control of CMV infection is largely accounted for by cellular immunity, involving various T-cell and B-cell subsets. In solid organ transplant patients, global suppression of innate and adaptive immunities by immunosuppressive agents limits immunological defense, including inhibition of natural killer cell activity with ongoing lowering of Ig levels and CMV-specific antibody titers. This is coupled with a short-term suppression of CMV-specific T cells, the extent and duration of which can predict risk of progression to CMV viremia. CMV immunoglobulin (CMVIG) preparations have the potential to exert immunomodulatory effects as well as providing passive immunization. Specific CMVIG antibodies and virus neutralization might be enhanced by modulation of dendritic cell activity and by a decrease in T-cell activation, effects which are of importance during the initial phase of infection. In summary, the role of CMVIG in reconstituting specific anti-CMV antibodies may be enhanced by some degree of modulation of the innate and adaptive immune responses, which could help to control some of the direct and indirect effects of CMV infection.

Health effects of a subway environment in healthy volunteers.

PubMed

Klepczyńska Nyström, A; Svartengren, M; Grunewald, J; Pousette, C; Rödin, I; Lundin, A; Sköld, C M; Eklund, A; Larsson, B-M

2010-08-01

Environmental particle exposure, often estimated as the particulate mass of particles with a diameter <10 microm, <2.5 microm or <1 microm (PM(10), PM(2.5) or PM(1)), is known to have a negative impact on the health of the population. Little is known about how the size and origin of particles influence the effects. We have previously shown that exposure to a road tunnel environment causes a cellular inflammatory response in the airways of healthy individuals. In the present study, our aim was to investigate potential airway health effects from exposure to a subway environment. 20 healthy volunteers were exposed to a subway and a control environment for 2 h, followed by measurements of lung function and the inflammatory response in the lower airways (bronchoscopy) and in the peripheral blood. No cellular response was found in the airways after exposure to the subway environment. In the blood, we found a statistically significant increase in fibrinogen and regulatory T-cells expressing CD4/CD25/FOXP3. Subway and road tunnel environments have similar levels of PM(10) and PM(2.5), whilst the concentrations of ultrafine particles, nitrogen monoxide and dioxide are lower in the subway. Although no cellular response was detected, the findings indicate a biological response to the subway environment. Our studies show that using gravimetric estimates of ambient particulate air pollution alone may have clear limitations in health-risk assessment.

Effects of helminths and Mycobacterium tuberculosis infection on HIV-1: a cellular immunological perspective.

PubMed

Mouser, Emily E I M; Pollakis, Georgios; Paxton, William A

2012-05-01

In many regions of the world, a high prevalence of HIV-1, helminthic and Mycobacterium tuberculosis (Mtb) infections can be found. Here, we summarize the types of immune responses induced and/or modulated by these pathogens and the consequences for HIV-1 disease. Helminths predominantly induce strong T helper (Th) 2 cellular responses which are downregulated in chronic disease. The anatomical niche populated by helminths plays a key factor in the effect these parasites have on HIV-1 transmission and subsequent replication. Gut-associated helminths have been found to increase HIV-1 transmission via the lesions they provide. In spite of this, the many immune modulatory molecules secreted by the parasites may inhibit or slow HIV-1 infection. In contrast, Mtb is mainly restricted to the lung and the Mtb-specific Th cells induced are highly susceptible to HIV-1 infection and replication. Antigens from both pathogens have immunomodulatory activity that can skew cellular immune responses in specific directions. The effect of helminths and Mtb on modulating immune responses is varied and complex with both their location and phenotype potentially influencing HIV-1 disease. These pathogens have evolved a complex array of molecules which have the capacity to modulate immunity and preserve pathogen survival.

Persistence at one year of age of antigen-induced cellular immune responses in preterm infants vaccinated against whooping cough: comparison of three different vaccines and effect of a booster dose.

PubMed

Vermeulen, Françoise; Dirix, Violette; Verscheure, Virginie; Damis, Eliane; Vermeylen, Danièle; Locht, Camille; Mascart, Françoise

2013-04-08

Due to their high risk of developing severe Bordetella pertussis (Bp) infections, it is recommended to immunize preterm infants at their chronological age. However, little is known about the persistence of their specific immune responses, especially of the cellular responses recognized to play a role in protection. We compared here the cellular immune responses to two major antigens of Bp between three groups of one year-old children born prematurely, who received for their primary vaccination respectively the whole cell vaccine Tetracoq(®) (TC), the acellular vaccine Tetravac(®) (TV), or the acellular vaccine Infanrix-hexa(®) (IR). Whereas most children had still detectable IFN-γ responses at one year of age, they were lower in the IR-vaccinated children compared to the two other groups. In contrast, both the TV- and the IR-vaccinated children displayed higher Th2-type immune responses, resulting in higher antigen-specific IFN-γ/IL-5 ratios in TC- than in TV- or IR-vaccinated children. The IFN-γ/IL-5 ratio of mitogen-induced cytokines was also lower in IR- compared to TC- or TV-vaccinated children. No major differences in the immune responses were noted after the booster compared to the pre-booster responses for each vaccine. The IR-vaccinated children had a persistently low specific Th1-type immune response associated with high specific Th2-type immune responses, resulting in lower antigen-specific IFN-γ/IL-5 ratios compared to the two other groups. We conclude that antigen-specific cellular immune responses persisted in one year-old children born prematurely and vaccinated during infancy at their chronological age, that a booster dose did not significantly boost the cellular immune responses, and that the Th1/Th2 balance of the immune responses is modulated by the different vaccines. Copyright © 2013 Elsevier Ltd. All rights reserved.

Particulate matter from both heavy fuel oil and diesel fuel shipping emissions show strong biological effects on human lung cells at realistic and comparable in vitro exposure conditions.

PubMed

Oeder, Sebastian; Kanashova, Tamara; Sippula, Olli; Sapcariu, Sean C; Streibel, Thorsten; Arteaga-Salas, Jose Manuel; Passig, Johannes; Dilger, Marco; Paur, Hanns-Rudolf; Schlager, Christoph; Mülhopt, Sonja; Diabaté, Silvia; Weiss, Carsten; Stengel, Benjamin; Rabe, Rom; Harndorf, Horst; Torvela, Tiina; Jokiniemi, Jorma K; Hirvonen, Maija-Riitta; Schmidt-Weber, Carsten; Traidl-Hoffmann, Claudia; BéruBé, Kelly A; Wlodarczyk, Anna J; Prytherch, Zoë; Michalke, Bernhard; Krebs, Tobias; Prévôt, André S H; Kelbg, Michael; Tiggesbäumker, Josef; Karg, Erwin; Jakobi, Gert; Scholtes, Sorana; Schnelle-Kreis, Jürgen; Lintelmann, Jutta; Matuschek, Georg; Sklorz, Martin; Klingbeil, Sophie; Orasche, Jürgen; Richthammer, Patrick; Müller, Laarnie; Elsasser, Michael; Reda, Ahmed; Gröger, Thomas; Weggler, Benedikt; Schwemer, Theo; Czech, Hendryk; Rüger, Christopher P; Abbaszade, Gülcin; Radischat, Christian; Hiller, Karsten; Buters, Jeroen T M; Dittmar, Gunnar; Zimmermann, Ralf

2015-01-01

Ship engine emissions are important with regard to lung and cardiovascular diseases especially in coastal regions worldwide. Known cellular responses to combustion particles include oxidative stress and inflammatory signalling. To provide a molecular link between the chemical and physical characteristics of ship emission particles and the cellular responses they elicit and to identify potentially harmful fractions in shipping emission aerosols. Through an air-liquid interface exposure system, we exposed human lung cells under realistic in vitro conditions to exhaust fumes from a ship engine running on either common heavy fuel oil (HFO) or cleaner-burning diesel fuel (DF). Advanced chemical analyses of the exhaust aerosols were combined with transcriptional, proteomic and metabolomic profiling including isotope labelling methods to characterise the lung cell responses. The HFO emissions contained high concentrations of toxic compounds such as metals and polycyclic aromatic hydrocarbon, and were higher in particle mass. These compounds were lower in DF emissions, which in turn had higher concentrations of elemental carbon ("soot"). Common cellular reactions included cellular stress responses and endocytosis. Reactions to HFO emissions were dominated by oxidative stress and inflammatory responses, whereas DF emissions induced generally a broader biological response than HFO emissions and affected essential cellular pathways such as energy metabolism, protein synthesis, and chromatin modification. Despite a lower content of known toxic compounds, combustion particles from the clean shipping fuel DF influenced several essential pathways of lung cell metabolism more strongly than particles from the unrefined fuel HFO. This might be attributable to a higher soot content in DF. Thus the role of diesel soot, which is a known carcinogen in acute air pollution-induced health effects should be further investigated. For the use of HFO and DF we recommend a reduction of carbonaceous soot in the ship emissions by implementation of filtration devices.

Particulate Matter from Both Heavy Fuel Oil and Diesel Fuel Shipping Emissions Show Strong Biological Effects on Human Lung Cells at Realistic and Comparable In Vitro Exposure Conditions

PubMed Central

Dilger, Marco; Paur, Hanns-Rudolf; Schlager, Christoph; Mülhopt, Sonja; Diabaté, Silvia; Weiss, Carsten; Stengel, Benjamin; Rabe, Rom; Harndorf, Horst; Torvela, Tiina; Jokiniemi, Jorma K.; Hirvonen, Maija-Riitta; Schmidt-Weber, Carsten; Traidl-Hoffmann, Claudia; BéruBé, Kelly A.; Wlodarczyk, Anna J.; Prytherch, Zoë; Michalke, Bernhard; Krebs, Tobias; Prévôt, André S. H.; Kelbg, Michael; Tiggesbäumker, Josef; Karg, Erwin; Jakobi, Gert; Scholtes, Sorana; Schnelle-Kreis, Jürgen; Lintelmann, Jutta; Matuschek, Georg; Sklorz, Martin; Klingbeil, Sophie; Orasche, Jürgen; Richthammer, Patrick; Müller, Laarnie; Elsasser, Michael; Reda, Ahmed; Gröger, Thomas; Weggler, Benedikt; Schwemer, Theo; Czech, Hendryk; Rüger, Christopher P.; Abbaszade, Gülcin; Radischat, Christian; Hiller, Karsten; Buters, Jeroen T. M.; Dittmar, Gunnar; Zimmermann, Ralf

2015-01-01

Background Ship engine emissions are important with regard to lung and cardiovascular diseases especially in coastal regions worldwide. Known cellular responses to combustion particles include oxidative stress and inflammatory signalling. Objectives To provide a molecular link between the chemical and physical characteristics of ship emission particles and the cellular responses they elicit and to identify potentially harmful fractions in shipping emission aerosols. Methods Through an air-liquid interface exposure system, we exposed human lung cells under realistic in vitro conditions to exhaust fumes from a ship engine running on either common heavy fuel oil (HFO) or cleaner-burning diesel fuel (DF). Advanced chemical analyses of the exhaust aerosols were combined with transcriptional, proteomic and metabolomic profiling including isotope labelling methods to characterise the lung cell responses. Results The HFO emissions contained high concentrations of toxic compounds such as metals and polycyclic aromatic hydrocarbon, and were higher in particle mass. These compounds were lower in DF emissions, which in turn had higher concentrations of elemental carbon (“soot”). Common cellular reactions included cellular stress responses and endocytosis. Reactions to HFO emissions were dominated by oxidative stress and inflammatory responses, whereas DF emissions induced generally a broader biological response than HFO emissions and affected essential cellular pathways such as energy metabolism, protein synthesis, and chromatin modification. Conclusions Despite a lower content of known toxic compounds, combustion particles from the clean shipping fuel DF influenced several essential pathways of lung cell metabolism more strongly than particles from the unrefined fuel HFO. This might be attributable to a higher soot content in DF. Thus the role of diesel soot, which is a known carcinogen in acute air pollution-induced health effects should be further investigated. For the use of HFO and DF we recommend a reduction of carbonaceous soot in the ship emissions by implementation of filtration devices. PMID:26039251

Addition of Alanyl-Glutamine to Dialysis Fluid Restores Peritoneal Cellular Stress Responses – A First-In-Man Trial

PubMed Central

Boehm, Michael; Herzog, Rebecca; Gruber, Katharina; Lichtenauer, Anton Michael; Kuster, Lilian; Csaicsich, Dagmar; Gleiss, Andreas; Alper, Seth L.; Aufricht, Christoph; Vychytil, Andreas

2016-01-01

Background Peritonitis and ultrafiltration failure remain serious complications of chronic peritoneal dialysis (PD). Dysfunctional cellular stress responses aggravate peritoneal injury associated with PD fluid exposure, potentially due to peritoneal glutamine depletion. In this randomized cross-over phase I/II trial we investigated cytoprotective effects of alanyl-glutamine (AlaGln) addition to glucose-based PDF. Methods In a prospective randomized cross-over design, 20 stable PD outpatients underwent paired peritoneal equilibration tests 4 weeks apart, using conventional acidic, single chamber 3.86% glucose PD fluid, with and without 8 mM supplemental AlaGln. Heat-shock protein 72 expression was assessed in peritoneal effluent cells as surrogate parameter of cellular stress responses, complemented by metabolomics and functional immunocompetence assays. Results AlaGln restored peritoneal glutamine levels and increased the primary outcome heat-shock protein expression (effect 1.51-fold, CI 1.07–2.14; p = 0.022), without changes in peritoneal ultrafiltration, small solute transport, or biomarkers reflecting cell mass and inflammation. Further effects were glutamine-like metabolomic changes and increased ex-vivo LPS-stimulated cytokine release from healthy donor peripheral blood monocytes. In patients with a history of peritonitis (5 of 20), AlaGln supplementation decreased dialysate interleukin-8 levels. Supplemented PD fluid also attenuated inflammation and enhanced stimulated cytokine release in a mouse model of PD-associated peritonitis. Conclusion We conclude that AlaGln-supplemented, glucose-based PD fluid can restore peritoneal cellular stress responses with attenuation of sterile inflammation, and may improve peritoneal host-defense in the setting of PD. PMID:27768727

A Unique Fungal Two-Component System Regulates Stress Responses, Drug Sensitivity, Sexual Development, and Virulence of Cryptococcus neoformans

PubMed Central

Bahn, Yong-Sun; Kojima, Kaihei; Cox, Gary M.

2006-01-01

The stress-activated mitogen-activated protein kinase (MAPK) pathway is widely used by eukaryotic organisms as a central conduit via which cellular responses to the environment effect growth and differentiation. The basidiomycetous human fungal pathogen Cryptococcus neoformans uniquely uses the stress-activated Pbs2-Hog1 MAPK system to govern a plethora of cellular events, including stress responses, drug sensitivity, sexual reproduction, and virulence. Here, we characterized a fungal “two-component” system that controls these fundamental cellular functions via the Pbs2-Hog1 MAPK cascade. A typical response regulator, Ssk1, modulated all Hog1-dependent phenotypes by controlling Hog1 phosphorylation, indicating that Ssk1 is the major upstream signaling component of the Pbs2-Hog1 pathway. A second response regulator, Skn7, governs sensitivity to Na+ ions and the antifungal agent fludioxonil, negatively controls melanin production, and functions independently of Hog1 regulation. To control these response regulators, C. neoformans uses multiple sensor kinases, including two-component–like (Tco) 1 and Tco2. Tco1 and Tco2 play shared and distinct roles in stress responses and drug sensitivity through the Hog1 MAPK system. Furthermore, each sensor kinase mediates unique cellular functions for virulence and morphological differentiation. Our findings highlight unique adaptations of this global two-component MAPK signaling cascade in a ubiquitous human fungal pathogen. PMID:16672377

Cellular cytotoxic response induced by highly purified multi-wall carbon nanotube in human lung cells.

PubMed

Tsukahara, Tamotsu; Haniu, Hisao

2011-06-01

Carbon nanotubes, a promising nanomaterial with unique characteristics, have applications in a variety of fields. The cytotoxic effects of carbon nanotubes are partially due to the induction of oxidative stress; however, the detailed mechanisms of nanotube cytotoxicity and their interaction with cells remain unclear. In this study, the authors focus on the acute toxicity of vapor-grown carbon fiber, HTT2800, which is one of the most highly purified multi-wall carbon nanotubes (MWCNT) by high-temperature thermal treatment. The authors exposed human bronchial epithelial cells (BEAS-2B) to HTT2800 and measured the cellular uptake, mitochondrial function, cellular LDH release, apoptotic signaling, reactive oxygen species (ROS) generation and pro-inflammatory cytokine release. The HTT2800-exposed cells showed cellular uptake of the carbon nanotube, increased cell death, enhanced DNA damage, and induced cytokine release. However, the exposed cells showed no obvious intracellular ROS generation. These cellular and molecular findings suggest that HTT2800 could cause a potentially adverse inflammatory response in BEAS-2B cells.

Mequindox induced cellular DNA damage via generation of reactive oxygen species.

PubMed

Liu, Jing; Ouyang, Man; Jiang, Jun; Mu, Peiqiang; Wu, Jun; Yang, Qi; Zhang, Caihui; Xu, Weiying; Wang, Lijuan; Huen, Michael S Y; Deng, Yiqun

2012-01-24

Mequindox, a quinoxaline-N-dioxide derivative that possesses antibacterial properties, has been widely used as a feed additive in the stockbreeding industry in China. While recent pharmacological studies have uncovered potential hazardous effects of mequindox, exactly how mequindox induces pathological changes and the cellular responses associated with its consumption remain largely unexplored. In this study, we investigated the cellular responses associated with mequindox treatment. We report here that mequindox inhibits cell proliferation by arresting cells at the G2/M phase of the cell cycle. Interestingly, this mequindox-associated deleterious effect on cell proliferation was observed in human, pig as well as chicken cells, suggesting that mequindox acts on evolutionarily conserved target(s). To further understand the mequindox-host interaction and the mechanism underlying mequindox-induced cell cycle arrest, we measured the cellular content of DNA damage, which is known to perturb cell proliferation and compromise cell survival. Accordingly, using γ-H2AX as a surrogate marker for DNA damage, we found that mequindox treatment induced cellular DNA damage, which paralleled the chemical-induced elevation of reactive oxygen species (ROS) levels. Importantly, expression of the antioxidant enzyme catalase partially alleviated these mequindox-associated effects. Taken together, our results suggest that mequindox cytotoxicity is attributable, in part, to its role as a potent inducer of DNA damage via ROS. © 2011 Elsevier B.V. All rights reserved.

Efficacy of adoptive cellular therapy in patients with gastric cancer: a meta-analysis.

PubMed

Shen, Dong; Liu, Zhi-Hao; Xu, Jia-Ning; Xu, Fang; Lin, Qin-Feng; Lin, Feng; Mao, Wei-Dong

2016-07-01

To systemically evaluate the efficacy and safety of adoptive cellular therapy for the treatment of gastric cancer (GC). We performed a systemic review and meta-analysis of nine eligible trials with GC and evaluated the effect of adoptive cellular therapy on the overall survival (OS) rate, T-cell subsets and adverse events. Overall, 829 patients were involved in the analysis. Adoptive cellular therapy significantly improved the OS rate compared with the control group. Meanwhile, we observed greatly increased percentages of CD3(+), CD4(+) and CD4(+)/CD8(+) in cellular therapy groups. Adoptive cellular therapy combined with adjuvant therapy resulted in significantly better OS rates, progression-free survival and T-lymphocyte responses in patients with GC.

Thyroid hormone effects on mitochondrial energetics.

PubMed

Harper, Mary-Ellen; Seifert, Erin L

2008-02-01

Thyroid hormones are the major endocrine regulators of metabolic rate, and their hypermetabolic effects are widely recognized. The cellular mechanisms underlying these metabolic effects have been the subject of much research. Thyroid hormone status has a profound impact on mitochondria, the organelles responsible for the majority of cellular adenosine triphosphate (ATP) production. However, mechanisms are not well understood. We review the effects of thyroid hormones on mitochondrial energetics and principally oxidative phosphorylation. Genomic and nongenomic mechanisms have been studied. Through the former, thyroid hormones stimulate mitochondriogenesis and thereby augment cellular oxidative capacity. Thyroid hormones induce substantial modifications in mitochondrial inner membrane protein and lipid compositions. Results are consistent with the idea that thyroid hormones activate the uncoupling of oxidative phosphorylation through various mechanisms involving inner membrane proteins and lipids. Increased uncoupling appears to be responsible for some of the hypermetabolic effects of thyroid hormones. ATP synthesis and turnover reactions are also affected. There appear to be complex relationships between mitochondrial proton leak mechanisms, reactive oxygen species production, and thyroid status. As the majority of studies have focused on the effects of thyroid status on rat liver preparations, there is still a need to address fundamental questions regarding thyroid hormone effects in other tissues and species.

Human Fetal Osteoblast Response on Poly(Methyl Methacrylate)/Polystyrene Demixed Thin Film Blends: Surface Chemistry Vs Topography Effects.

PubMed

D'Sa, Raechelle A; Raj, Jog; Dickinson, Peter J; McCabe, Fiona; Meenan, Brian J

2016-06-22

Recent advances in materials sciences have allowed for the development and fabrication of biomaterials that are capable of providing requisite cues to instigate cells to respond in a predictable fashion. We have developed a series of poly(methyl methacrylate)/polystyrene (PMMA/PS) polymer demixed thin films with nanotopographies ranging from nanoislands to nanopits to study the response of human fetal osteoblast cells (hFOBs). When PMMA was in excess in the blend composition, a nanoisland topography dominated, whereas a nanopit topography dominated when PS was in excess. PMMA was found to segregate to the top of the nanoisland morphology with PS preferring the substrate interface. To further ascertain the effects of surface chemistry vs topography, we plasma treated the polymer demixed films using an atmospheric pressure dielectric barrier discharge reactor to alter the surface chemistry. Our results have shown that hFOBs did not have an increased short-term cellular response on pristine polymer demixed surfaces. However, increasing the hydrophilicty/wettability of the surfaces by oxygen functionalization causes an increase in the cellular response. These results indicate that topography alone is not sufficient to induce a positive cellular response, but the underlying surface chemistry is also important in regulating cell function.

Immunogenicity and safety of xenogeneic vascular endothelial growth factor receptor-2 DNA vaccination in mice and dogs

PubMed Central

Denies, Sofie; Cicchelero, Laetitia; Polis, Ingeborgh; Sanders, Niek N.

2016-01-01

Vascular endothelial growth factor receptor-2 (VEGFR-2) is an attractive target in oncology due to its crucial role in angiogenesis. In this study a DNA vaccine coding for human VEGFR-2 was evaluated in healthy mice and dogs, administered by intradermal injection and electroporation. In mice, three doses and vaccination schedules were evaluated. Cellular immune responses were measured by intracellular IFN-gamma staining and a cytotoxicity assay and antibodies by ELISA. Safety was assessed by measuring regulatory T cells and myeloid derived suppressor cells and a wound healing assay. The vaccine was subsequently evaluated in dogs, which were vaccinated three times with 100μg. Cellular immune responses were measured by intracellular IFN-gamma staining and antibodies by a flow cytometric assay. In mice, maximal cellular responses were observed after two vaccinations with 5μg. Humoral responses continued to increase with higher dose and number of vaccinations. No abnormalities in the measured safety parameters were observed. The vaccine was also capable of eliciting a cellular and humoral immune response in dogs. No adverse effects were observed, but tolerability of the electroporation was poor. This study will facilitate the evaluation of the vaccine in tumor bearing animals, ranging from rodent models to dogs with spontaneous tumors. PMID:26871296

Protein O-GlcNAcylation: A critical regulator of the cellular response to stress.

PubMed

Chatham, John C; Marchase, Richard B

2010-01-01

The post-translational modification of serine and threonine residues of nuclear and cytoplasmic proteins by the O-linked attachment of the monosaccharide ß-N-acetyl-glucosamine (O-GlcNAc) is a highly dynamic and ubiquitous protein modification that plays a critical role in regulating numerous biological processes. Much of our understanding of the mechanisms underlying the role of O-GlcNAc on cellular function has been in the context of chronic disease processes. However, there is increasing evidence that O-GlcNAc levels are increased in response to stress and that acute augmentation of this response is cytoprotective, at least in the short term. Conversely, a reduction in O-GlcNAc levels appears to be associated with decreased cell survival in response to an acute stress. Here we summarize our current understanding of protein O-GlcNAcylation on the cellular response to stress and in mediating cellular protective mechanisms focusing primarily on the cardiovascular system as an example. We consider the potential link between O-GlcNAcylation and cardiomyocyte calcium homeostasis and explore the parallels between O-GlcNAc signaling and redox signaling. We also discuss the apparent paradox between the reported adverse effects of increased O-GlcNAcylation with its recently reported role in mediating cell survival mechanisms.

Distinct pathways of humoral and cellular immunity induced with the mucosal administration of a nanoemulsion adjuvant.

PubMed

Bielinska, Anna U; Makidon, Paul E; Janczak, Katarzyna W; Blanco, Luz P; Swanson, Benjamin; Smith, Douglas M; Pham, Tiffany; Szabo, Zsuzsanna; Kukowska-Latallo, Jolanta F; Baker, James R

2014-03-15

Nasal administration of an oil-in-water nanoemulsion (NE) adjuvant W805EC produces potent systemic and mucosal, Th-1- and Th-17-balanced cellular responses. However, its molecular mechanism of action has not been fully characterized and is of particular interest because NE does not contain specific ligands for innate immune receptors. In these studies, we demonstrate that W805EC NE adjuvant activates innate immunity, induces specific gene transcription, and modulates NF-κB activity via TLR2 and TLR4 by a mechanism that appears to be distinct from typical TLR agonists. Nasal immunization with NE-based vaccine showed that the TLR2, TLR4, and MyD88 pathways and IL-12 and IL-12Rβ1 expression are not required for an Ab response, but they are essential for the induction of balanced Th-1 polarization and Th-17 cellular immunity. NE adjuvant induces MHC class II, CD80, and CD86 costimulatory molecule expression and dendritic cell maturation. Further, upon immunization with NE, adjuvant mice deficient in the CD86 receptor had normal Ab responses but significantly reduced Th-1 cellular responses, whereas animals deficient in both CD80 and CD86 or lacking CD40 failed to produce either humoral or cellular immunity. Overall, our data show that intranasal administration of Ag with NE induces TLR2 and TLR4 activation along with a MyD88-independent Ab response and a MyD88-dependent Th-1 and Th-17 cell-mediated immune response. These findings suggest that the unique properties of NE adjuvant may offer novel opportunities for understanding previously unrecognized mechanisms of immune activation important for generating effective mucosal and systemic immune responses.

Adrenergic Receptor Stimulation Prevents Radiation-Induced DNA Strand Breaks, Apoptosis and Gene Expression in Simulated Microgravity

NASA Technical Reports Server (NTRS)

Moreno-Villanueva, Maria; Krieger, Stephanie; Feiveson, Alan; Kovach, Annie Marie; Buerkle, Alexander; Wu, Honglu

2017-01-01

Under Earth gravity conditions cellular damage can be counteracted by activation of the physiological defense mechanisms or through medical interventions. The mode of action of both, physiological response and medical interventions can be affected by microgravity leading to failure in repairing the damage. There are many studies reporting the effects of microgravity and/or radiation on cellular functions. However, little is known about the synergistic effects on cellular response to radiation when other endogenous cellular stress-response pathways are previously activated. Here, we investigated whether previous stimulation of the adrenergic receptor, which modulates immune response, affects radiation-induced apoptosis in immune cells under simulated microgravity conditions. Peripheral blood mononuclear cells (PBMCs) were stimulated with isoproterenol (a sympathomimetic drug) and exposed to 0.8 or 2Gy gamma-radiation in simulated microgravity versus Earth gravity. Expression of genes involved in adrenergic receptor pathways, DNA repair and apoptosis as well as the number of apoptotic cells and DNA strand breaks were determined. Our results showed that, under simulated microgravity conditions, previous treatment with isoproterenol prevented radiation-induced i) gene down regulation, ii) DNA strand breaks formation and iii) apoptosis induction. Interestedly, we found a radiation-induced increase of adrenergic receptor gene expression, which was also abolished in simulated microgravity. Understanding the mechanisms of isoproterenol-mediated radioprotection in simulated microgravity can help to develop countermeasures for space-associated health risks as well as radio-sensitizers for cancer therapy.

Th1 stimulatory proteins of Leishmania donovani: comparative cellular and protective responses of rTriose phosphate isomerase, rProtein disulfide isomerase and rElongation factor-2 in combination with rHSP70 against visceral leishmaniasis.

PubMed

Jaiswal, Anil Kumar; Khare, Prashant; Joshi, Sumit; Kushawaha, Pramod Kumar; Sundar, Shyam; Dube, Anuradha

2014-01-01

In visceral leishmaniasis, the recovery from the disease is always associated with the generation of Th1-type of cellular responses. Based on this, we have previously identified several Th1-stimulatory proteins of Leishmania donovani -triose phosphate isomerase (TPI), protein disulfide isomerase (PDI) and elongation factor-2 (EL-2) etc. including heat shock protein 70 (HSP70) which induced Th1-type of cellular responses in both cured Leishmania patients/hamsters. Since, HSPs, being the logical targets for vaccines aimed at augmenting cellular immunity and can be early targets in the immune response against intracellular pathogens; they could be exploited as vaccine/adjuvant to induce long-term immunity more effectively. Therefore, in this study, we checked whether HSP70 can further enhance the immunogenicity and protective responses of the above said Th1-stimulatory proteins. Since, in most of the studies, immunogenicity of HSP70 of L. donovani was assessed in native condition, herein we generated recombinant HSP70 and tested its potential to stimulate immune responses in lymphocytes of cured Leishmania infected hamsters as well as in the peripheral blood mononuclear cells (PBMCs) of cured patients of VL either individually or in combination with above mentioned recombinant proteins. rLdHSP70 alone elicited strong cellular responses along with remarkable up-regulation of IFN-γ and IL-12 cytokines and extremely lower level of IL-4 and IL-10. Among the various combinations, rLdHSP70 + rLdPDI emerged as superior one augmenting improved cellular responses followed by rLdHSP70 + rLdEL-2. These combinations were further evaluated for its protective potential wherein rLdHSP70 + rLdPDI again conferred utmost protection (∼80%) followed by rLdHSP70 + rLdEL-2 (∼75%) and generated a strong cellular immune response with significant increase in the levels of iNOS transcript as well as IFN-γ and IL-12 cytokines which was further supported by the high level of IgG2 antibody in vaccinated animals. These observations indicated that vaccine(s) based on combination of HSP70 with Th1-stimulatory protein(s) may be a viable proposition against intracellular pathogens.

Th1 Stimulatory Proteins of Leishmania donovani: Comparative Cellular and Protective Responses of rTriose Phosphate Isomerase, rProtein Disulfide Isomerase and rElongation Factor-2 in Combination with rHSP70 against Visceral Leishmaniasis

PubMed Central

Jaiswal, Anil Kumar; Khare, Prashant; Joshi, Sumit; Kushawaha, Pramod Kumar; Sundar, Shyam; Dube, Anuradha

2014-01-01

In visceral leishmaniasis, the recovery from the disease is always associated with the generation of Th1-type of cellular responses. Based on this, we have previously identified several Th1-stimulatory proteins of Leishmania donovani -triose phosphate isomerase (TPI), protein disulfide isomerase (PDI) and elongation factor-2 (EL-2) etc. including heat shock protein 70 (HSP70) which induced Th1-type of cellular responses in both cured Leishmania patients/hamsters. Since, HSPs, being the logical targets for vaccines aimed at augmenting cellular immunity and can be early targets in the immune response against intracellular pathogens; they could be exploited as vaccine/adjuvant to induce long-term immunity more effectively. Therefore, in this study, we checked whether HSP70 can further enhance the immunogenicity and protective responses of the above said Th1-stimulatory proteins. Since, in most of the studies, immunogenicity of HSP70 of L. donovani was assessed in native condition, herein we generated recombinant HSP70 and tested its potential to stimulate immune responses in lymphocytes of cured Leishmania infected hamsters as well as in the peripheral blood mononuclear cells (PBMCs) of cured patients of VL either individually or in combination with above mentioned recombinant proteins. rLdHSP70 alone elicited strong cellular responses along with remarkable up-regulation of IFN-γ and IL-12 cytokines and extremely lower level of IL-4 and IL-10. Among the various combinations, rLdHSP70 + rLdPDI emerged as superior one augmenting improved cellular responses followed by rLdHSP70 + rLdEL-2. These combinations were further evaluated for its protective potential wherein rLdHSP70 + rLdPDI again conferred utmost protection (∼80%) followed by rLdHSP70 + rLdEL-2 (∼75%) and generated a strong cellular immune response with significant increase in the levels of iNOS transcript as well as IFN-γ and IL-12 cytokines which was further supported by the high level of IgG2 antibody in vaccinated animals. These observations indicated that vaccine(s) based on combination of HSP70 with Th1-stimulatory protein(s) may be a viable proposition against intracellular pathogens. PMID:25268700

Cell Proliferation, Reactive Oxygen and Cellular Glutathione

PubMed Central

Day, Regina M.; Suzuki, Yuichiro J.

2005-01-01

A variety of cellular activities, including metabolism, growth, and death, are regulated and modulated by the redox status of the environment. A biphasic effect has been demonstrated on cellular proliferation with reactive oxygen species (ROS)—especially hydrogen peroxide and superoxide—in which low levels (usually submicromolar concentrations) induce growth but higher concentrations (usually >10–30 micromolar) induce apoptosis or necrosis. This phenomenon has been demonstrated for primary, immortalized and transformed cell types. However, the mechanism of the proliferative response to low levels of ROS is not well understood. Much of the work examining the signal transduction by ROS, including H2O2, has been performed using doses in the lethal range. Although use of higher ROS doses have allowed the identification of important signal transduction pathways, these pathways may be activated by cells only in association with ROS-induced apoptosis and necrosis, and may not utilize the same pathways activated by lower doses of ROS associated with increased cell growth. Recent data has shown that low levels of exogenous H2O2 up-regulate intracellular glutathione and activate the DNA binding activity toward antioxidant response element. The modulation of the cellular redox environment, through the regulation of cellular glutathione levels, may be a part of the hormetic effect shown by ROS on cell growth. PMID:18648617

Altered cellular magnesium responsiveness to hyperglycemia in hypertensive subjects.

PubMed

Barbagallo, M; Dominguez, L J; Bardicef, O; Resnick, L M

2001-09-01

Previous studies by our group have identified ionic aspects of insulin resistance in hypertension, in which cellular responses to insulin were influenced by the basal intracellular ionic environment-the lower the cytosolic free magnesium (Mg(i)), the less Mg(i) increased following insulin stimulation. To investigate whether this ionic insulin resistance represents a more general abnormality of cellular responsiveness in hypertension, we studied Mg(i) responses to nonhormonal signals such as hyperglycemia (15 mmol/L) and used (31)P-nuclear magnetic resonance (NMR) spectroscopy to measure Mg(i) in erythrocytes from normal (NL, n=14) and hypertensive (HTN, n=12) subjects before and 30, 60, 120, and 180 minutes after in vitro glucose incubations. Basal Mg(i) levels were significantly lower in HTN subjects than in NL subjects (169+/-10 versus 205+/-8 micromol.L(-1), P<0.01). In NL cells, hyperglycemia significantly lowered Mg(i), from 205+/-8 micromol.L(-1) (basal, T=0) to 181+/-8, 162+/-6, 152+/-7, and 175+/-9 micromol.L(-1) (T=30, 60, 120, and 180, respectively; P<0.005 versus T=0 at all times). In HTN cells, maximal Mg(i) responses to hyperglycemia were blunted, from 169+/-10 micromol.L(-1) (basal, T=0) to 170+/-11, 179+/-12, 181+/-14, and 173+/-15 micromol.L(-1) (T=30, 60, 120, and 180, respectively; P=NS versus T=0 at all times). For all subjects, Mg(i) responses to hyperglycemia were closely related to basal Mg(i) levels: the higher the Mg(i), the greater the response (n=26, r=0.620, P<0.001). Thus, (1) erythrocytes from hypertensive vis-à-vis normotensive subjects are resistant to the ionic effects of extracellular hyperglycemia on Mg(i) levels, and (2) cellular ionic responses to glucose depend on the basal Mg(i) environment. Altogether, these data support a role for altered extracellular glucose levels in regulating cellular magnesium metabolism and also suggest the importance of ionic factors in determining cellular responsiveness to nonhormonal as well as hormonal signals.

Changing partners at the dance

PubMed Central

Kallal, Lara E.; Biron, Christine A.

2013-01-01

Differential use of cellular and molecular components shapes immune responses, but understanding of how these are regulated to promote defense and health during infections is still incomplete. Examples include signaling from members of the Janus activated kinase-signal transducer and activator of transcription (JAK-STAT) cytokine family. Following receptor stimulation, individual JAK-STAT cytokines have preferences for particular key STAT molecules to lead to specific cellular responses. Certain of these cytokines, however, can conditionally activate alternative STATs as well as elicit pleiotropic and paradoxical effects. Studies examining basal and infection conditions are revealing intrinsic and induced cellular differences in various intracellular STAT concentrations to control the biological consequences of cytokine exposure. The system can be likened to changing partners at a dance based on competition and relative availability, and sets a framework for understanding the particular conditions promoting subset biological functions of cytokines as needed during evolving immune responses to infections. PMID:24058795

7th International Workshop on Microbeam Probes of Cellular Radiation Response

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brenner, David J.

2009-07-21

The extended abstracts that follow present a summary of the Proceedings of the 7th International Workshop: Microbeam Probes of Cellular Radiation Response, held at Columbia University’s Kellogg Center in New York City on March 15–17, 2006. These International Workshops on Microbeam Probes of Cellular Radiation Response have been held regularly since 1993 (1–5). Since the first workshop, there has been a rapid growth (see Fig. 1) in the number of centers developing microbeams for radiobiological research, and worldwide there are currently about 30 microbeams in operation or under development. Single-cell/single-particle microbeam systems can deliver beams of different ionizing radiations withmore » a spatial resolution of a few micrometers down to a few tenths of a micrometer. Microbeams can be used to addressquestions relating to the effects of low doses of radiation (a single radiation track traversing a cell or group of cells), to probe subcellular targets (e.g. nucleus or cytoplasm), and to address questions regarding the propagation of information about DNA damage (for example, the radiation-induced bystander effect). Much of the recent research using microbeams has been to study low-dose effects and ‘‘non-targeted’’ responses such as bystander effects, genomic instability and adaptive responses. This Workshop provided a forum to assess the current state of microbeam technology and current biological applications and to discuss future directions for development, both technological and biological. Over 100 participants reviewed the current state of microbeam research worldwide and reported on new technological developments in the fields of both physics and biology.« less

Focus small to find big - the microbeam story.

PubMed

Wu, Jinhua; Hei, Tom K

2017-08-29

Even though the first ultraviolet microbeam was described by S. Tschachotin back in 1912, the development of sophisticated micro-irradiation facilities only began to flourish in the late 1980s. In this article, we highlight significant microbeam experiments, describe the latest microbeam irradiator configurations and critical discoveries made by using the microbeam apparatus. Modern radiological microbeams facilities are capable of producing a beam size of a few micrometers, or even tens of nanometers in size, and can deposit radiation with high precision within a cellular target. In the past three decades, a variety of microbeams has been developed to deliver a range of radiations including charged particles, X-rays, and electrons. Despite the original intention for their development to measure the effects of a single radiation track, the ability to target radiation with microbeams at sub-cellular targets has been extensively used to investigate radiation-induced biological responses within cells. Studies conducted using microbeams to target specific cells in a tissue have elucidated bystander responses, and further studies have shown reactive oxygen species (ROS) and reactive nitrogen species (RNS) play critical roles in the process. The radiation-induced abscopal effect, which has a profound impact on cancer radiotherapy, further reaffirmed the importance of bystander effects. Finally, by targeting sub-cellular compartments with a microbeam, we have reported cytoplasmic-specific biological responses. Despite the common dogma that nuclear DNA is the primary target for radiation-induced cell death and carcinogenesis, studies conducted using microbeam suggested that targeted cytoplasmic irradiation induces mitochondrial dysfunction, cellular stress, and genomic instability. A more recent development in microbeam technology includes application of mouse models to visualize in vivo DNA double-strand breaks. Microbeams are making important contributions towards our understanding of radiation responses in cells and tissue models.

Cell-to-cell communication and cellular environment alter the somatostatin status of delta cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kelly, Catriona, E-mail: catriona.kelly@qub.ac.uk; Flatt, Peter R.; McClenaghan, Neville H.

2010-08-20

Research highlights: {yields} TGP52 cells display enhanced functionality in pseudoislet form. {yields} Somatostatin content was reduced, but secretion increased in high glucose conditions. {yields} Cellular interactions and environment alter the somatostatin status of TGP52 cells. -- Abstract: Introduction: Somatostatin, released from pancreatic delta cells, is a potent paracrine inhibitor of insulin and glucagon secretion. Islet cellular interactions and glucose homeostasis are essential to maintain normal patterns of insulin secretion. However, the importance of cell-to-cell communication and cellular environment in the regulation of somatostatin release remains unclear. Methods: This study employed the somatostatin-secreting TGP52 cell line maintained in DMEM:F12 (17.5 mMmore » glucose) or DMEM (25 mM glucose) culture media. The effect of pseudoislet formation and culture medium on somatostatin content and release in response to a variety of stimuli was measured by somatostatin EIA. In addition, the effect of pseudoislet formation on cellular viability (MTT and LDH assays) and proliferation (BrdU ELISA) was determined. Results: TGP52 cells readily formed pseudoislets and showed enhanced functionality in three-dimensional form with increased E-cadherin expression irrespective of the culture environment used. However, culture in DMEM decreased cellular somatostatin content (P < 0.01) and increased somatostatin secretion in response to a variety of stimuli including arginine, calcium and PMA (P < 0.001) when compared with cells grown in DMEM:F12. Configuration of TGP52 cells as pseudoislets reduced the proliferative rate and increased cellular cytotoxicity irrespective of culture medium used. Conclusions: Somatostatin secretion is greatly facilitated by cell-to-cell interactions and E-cadherin expression. Cellular environment and extracellular glucose also significantly influence the function of delta cells.« less

Activity against Mycobacterium tuberculosis with concomitant induction of cellular immune responses by a tetraaza-macrocycle with acetate pendant arms.

PubMed

David, S; Ordway, D; Arroz, M J; Costa, J; Delgado, R

2001-01-01

The novel tetraaza-macrocyclic compound 3,7,11-tris(carboxymethyl)-3,7,11,17-tetraaza-bicyclo[11.3.1]heptadeca-1(17),13,15-triene, abbreviated as ac3py14, was investigated for its activity against Mycobacterium tuberculosis and for induction of protective cellular immune responses. Perspective results show that ac3py14 and its Fe3+ 1:1 complex, [Fe(ac3py14)], inhibited radiometric growth of several strains of M. tuberculosis. Inhibition with 25 microg/mL varied from 99% for H37Rv to 80% and above for multiple drug-resistant clinical isolates. The capacity of ac3py14 to elicit a beneficial immune response without cellular apoptosis was assessed and compared to the effects of virulent M. tuberculosis. The present study produces evidence that after stimulation with ac3py14 there was significant production of interferon gamma (IFN-gamma), whereas the production of interleukin-5 (IL-5) remained low, and there was development of a memory population (CD45RO). The level of binding of Annexin V, a marker of apoptosis, was not sufficient to result in toxic effects toward alphabeta and gammadelta T cells and CD14+ macrophages. This preliminary study is the first report of a compound that simultaneously exerts an inhibitory effect against M. tuberculosis and induces factors associated with protective immune responses.

Integrated multi-biomarker responses in two dreissenid species following metal and thermal cross-stress.

PubMed

Potet, Marine; Devin, Simon; Pain-Devin, Sandrine; Rousselle, Philippe; Giambérini, Laure

2016-11-01

With current global changes, the combination of several stressors such as temperature and contaminants may impact species distribution and ecosystem functioning. In this study, we evaluated the combined impact of two metals (Ni and Cr) with a thermal stress (from 12 to 17 °C) on biomarker responses in two bivalves, Dreissena rostriformis bugensis and Dreissena polymorpha. Biomarkers are informative tools to evaluate exposure and effects of stressors on organisms. The set of 14 biomarkers measured here was representative of both physiologic (filtration activity) and cellular antioxidant and detoxification mechanisms. Our aim was to study the response pattern of both species, and its meaning in terms of invasive potential. The implications for the use of these mussels in environmental monitoring are also discussed. Results evidenced that the two species do not respond to multiple stressors in the same way. Indeed, the effects of contamination on biomarker responses were more marked for D. polymorpha, especially under nickel exposure. While we cannot conclude as to the effect of temperature, invasiveness could be influenced by species sensitivity to contaminants. The physiological and cellular differences between D. polymorpha and D. r. bugensis might also be of concern for environmental risk assessment. The two species present differential bioaccumulation patterns, filtration activity and cellular biomarker responses. If D. polymorpha populations decline, their substitution by D. r. bugensis for biomonitoring or laboratory studies will not be possible without a deeper understanding of biomarker responses of the new invasive. Copyright © 2016 Elsevier Ltd. All rights reserved.

Early spatiotemporal-specific changes in intermediate signals are predictive of cytotoxic sensitivity to TNFα and co-treatments

NASA Astrophysics Data System (ADS)

Loo, Lit-Hsin; Bougen-Zhukov, Nicola Michelle; Tan, Wei-Ling Cecilia

2017-03-01

Signaling pathways can generate different cellular responses to the same cytotoxic agents. Current quantitative models for predicting these differential responses are usually based on large numbers of intracellular gene products or signals at different levels of signaling cascades. Here, we report a study to predict cellular sensitivity to tumor necrosis factor alpha (TNFα) using high-throughput cellular imaging and machine-learning methods. We measured and compared 1170 protein phosphorylation events in a panel of human lung cancer cell lines based on different signals, subcellular regions, and time points within one hour of TNFα treatment. We found that two spatiotemporal-specific changes in an intermediate signaling protein, p90 ribosomal S6 kinase (RSK), are sufficient to predict the TNFα sensitivity of these cell lines. Our models could also predict the combined effects of TNFα and other kinase inhibitors, many of which are not known to target RSK directly. Therefore, early spatiotemporal-specific changes in intermediate signals are sufficient to represent the complex cellular responses to these perturbations. Our study provides a general framework for the development of rapid, signaling-based cytotoxicity screens that may be used to predict cellular sensitivity to a cytotoxic agent, or identify co-treatments that may sensitize or desensitize cells to the agent.

Early spatiotemporal-specific changes in intermediate signals are predictive of cytotoxic sensitivity to TNFα and co-treatments

PubMed Central

Loo, Lit-Hsin; Bougen-Zhukov, Nicola Michelle; Tan, Wei-Ling Cecilia

2017-01-01

Signaling pathways can generate different cellular responses to the same cytotoxic agents. Current quantitative models for predicting these differential responses are usually based on large numbers of intracellular gene products or signals at different levels of signaling cascades. Here, we report a study to predict cellular sensitivity to tumor necrosis factor alpha (TNFα) using high-throughput cellular imaging and machine-learning methods. We measured and compared 1170 protein phosphorylation events in a panel of human lung cancer cell lines based on different signals, subcellular regions, and time points within one hour of TNFα treatment. We found that two spatiotemporal-specific changes in an intermediate signaling protein, p90 ribosomal S6 kinase (RSK), are sufficient to predict the TNFα sensitivity of these cell lines. Our models could also predict the combined effects of TNFα and other kinase inhibitors, many of which are not known to target RSK directly. Therefore, early spatiotemporal-specific changes in intermediate signals are sufficient to represent the complex cellular responses to these perturbations. Our study provides a general framework for the development of rapid, signaling-based cytotoxicity screens that may be used to predict cellular sensitivity to a cytotoxic agent, or identify co-treatments that may sensitize or desensitize cells to the agent. PMID:28272488

Sex-dependent effects of nutrition on telomere dynamics in zebra finches (Taeniopygia guttata)

PubMed Central

Noguera, Jose C.; Metcalfe, Neil B.; Boner, Winnie; Monaghan, Pat

2015-01-01

At a cellular level, oxidative stress is known to increase telomere attrition, and hence cellular senescence and risk of disease. It has been proposed that dietary micronutrients play an important role in telomere protection due to their antioxidant properties. We experimentally manipulated dietary micronutrients during early life in zebra finches (Taeniopygia guttata). We found no effects of micronutrient intake on telomere loss during chick growth. However, females given a diet high in micronutrients during sexual maturation showed reduced telomere loss; there was no such effect in males. These results suggest that micronutrients may influence rates of cellular senescence, but differences in micronutrient requirement and allocation strategies, probably linked to the development of sexual coloration, may underlie sex differences in response. PMID:25716087

Analysis of high-throughput screening reveals the effect of surface topographies on cellular morphology.

PubMed

Hulsman, Marc; Hulshof, Frits; Unadkat, Hemant; Papenburg, Bernke J; Stamatialis, Dimitrios F; Truckenmüller, Roman; van Blitterswijk, Clemens; de Boer, Jan; Reinders, Marcel J T

2015-03-01

Surface topographies of materials considerably impact cellular behavior as they have been shown to affect cell growth, provide cell guidance, and even induce cell differentiation. Consequently, for successful application in tissue engineering, the contact interface of biomaterials needs to be optimized to induce the required cell behavior. However, a rational design of biomaterial surfaces is severely hampered because knowledge is lacking on the underlying biological mechanisms. Therefore, we previously developed a high-throughput screening device (TopoChip) that measures cell responses to large libraries of parameterized topographical material surfaces. Here, we introduce a computational analysis of high-throughput materiome data to capture the relationship between the surface topographies of materials and cellular morphology. We apply robust statistical techniques to find surface topographies that best promote a certain specified cellular response. By augmenting surface screening with data-driven modeling, we determine which properties of the surface topographies influence the morphological properties of the cells. With this information, we build models that predict the cellular response to surface topographies that have not yet been measured. We analyze cellular morphology on 2176 surfaces, and find that the surface topography significantly affects various cellular properties, including the roundness and size of the nucleus, as well as the perimeter and orientation of the cells. Our learned models capture and accurately predict these relationships and reveal a spectrum of topographies that induce various levels of cellular morphologies. Taken together, this novel approach of high-throughput screening of materials and subsequent analysis opens up possibilities for a rational design of biomaterial surfaces. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Anti-tumor response with immunologically modified carbon nanotubes and phototherapy

NASA Astrophysics Data System (ADS)

Acquaviva, Joseph T.; Zhou, Feifan; Boarman, Ellen; Chen, Wei R.

2013-02-01

While successes of different cancer therapies have been achieved in various degrees a systemic immune response is needed to effectively treat late-stage, metastatic cancers, and to establish long-term tumor resistance in the patients. A novel method for combating metastatic cancers has been developed using immunologically modified carbon nanotubes in conjunction with phototherapy. Glycated chitosan (GC) is a potent immunological adjuvant capable of increasing host immune responses, including antigen presentation by activation of dendritic cells (DCs) and causing T cell proliferation. GC is also an effective surfactant for nanomaterials. By combining single-walled carbon nanotubes (SWNTs) and GC, immunologically modified carbon nanotubes (SWNT-GC) were constructed. The SWNT-GC suspension retains the enhanced light absorption properties in the near infrared (NIR) region and the ability to enter cells, which are characteristic of SWNTs. The SWNT-GC also retains the immunological properties of GC. Cellular SWNT-GC treatments increased macrophage activity, DC activation and T cell proliferation. When cellular SWNT-GC was irradiated with a laser of an appropriate wavelength, these immune activities could be enhanced. The combination of laser irradiation and SWNT-GC induced cellular toxicity in targeted tumor cells, leading to a systemic antitumor response. Immunologically modified carbon nanotubes in conjunction with phototherapy is a novel and promising method to produce a systemic immune response for the treatment of metastatic cancers.

Cellular glucose-6-phosphate dehydrogenase (G6PD) status modulates the effects of nitric oxide (NO) on human foreskin fibroblasts.

PubMed

Cheng, M L; Ho, H Y; Liang, C M; Chou, Y H; Stern, A; Lu, F J; Chiu, D T

2000-06-23

Glucose-6-phosphate dehydrogenase (G6PD) plays an important role in cellular redox homeostasis, which is crucial for cell survival. In the present study, we found that G6PD status determines the response of cells exposed to nitric oxide (NO) donor. Treatment with NO donor, sodium nitroprusside (SNP), caused apoptosis in G6PD-deficient human foreskin fibroblasts (HFF1), whereas it was growth stimulatory in the normal counterpart (HFF3). Such effects were abolished by NO scavengers like hemoglobin. Ectopic expression of G6PD in HFF1 cells switched the cellular response to NO from apoptosis to growth stimulation. Experiments with 1H-¿1,2,4ŏxadiazolo¿4, 3-aquinoxalin-1-one and 8-bromo-cGMP showed that the effects of NO on HFF1 and HFF3 cells were independent of cGMP signalling pathway. Intriguingly, trolox prevented the SNP-induced apoptosis in HFF1 cells. These data demonstrate that G6PD plays a critical role in regulation of cell growth and survival.

Enhancing immune responses to inactivated porcine parvovirus oil emulsion vaccine by co-inoculating porcine transfer factor in mice.

PubMed

Wang, Rui-ning; Wang, Ya-bin; Geng, Jing-wei; Guo, Dong-hui; Liu, Fang; Chen, Hong-ying; Zhang, Hong-ying; Cui, Bao-an; Wei, Zhan-yong

2012-07-27

Inactivated porcine parvovirus (PPV) vaccines are available commercially and widely used in the breeding herds. However, inactivated PPV vaccines have deficiencies in induction of specific cellular immune response. Transfer factor (TF) is a material that obtained from the leukocytes, and is a novel immune-stimulatory reagent that as a modulator of the immune system. In this study, the immunogenicity of PPV oil emulsion vaccine and the immuno-regulatory activities of TF were investigated. The inactivated PPV oil emulsion vaccines with or without TF were inoculated into BALB/c mice by subcutaneous injection. Then humoral and cellular immune responses were evaluated by indirect enzyme-linked immunosorbent assays (ELISA), fluorescence-activated cell sorter analyses (FACS). The results showed that the PPV specific immune responses could be evoked in mice by inoculating with PPV oil emulsion vaccine alone or by co-inoculation with TF. The cellular immune response levels in the co-inoculation groups were higher than those groups receiving the PPV oil emulsion vaccine alone, with the phenomena of higher level of IFN-γ, a little IL-6 and a trace of IL-4 in serum, and a vigorous T-cell response. However, there was no significant difference in antibody titers between TF synergy inactivated vaccine and the inactivated vaccine group (P>0.05). In conclusion, these results suggest that TF possess better cellular immune-enhancing capability and would be exploited into an effective immune-adjuvant for inactivated vaccines. Copyright © 2012 Elsevier Ltd. All rights reserved.

10-Oxo-trans-11-octadecenoic acid generated from linoleic acid by a gut lactic acid bacterium Lactobacillus plantarum is cytoprotective against oxidative stress

DOE Office of Scientific and Technical Information (OSTI.GOV)

Furumoto, Hidehiro; Nanthirudjanar, Tharnath; Kume, Toshiaki

Oxidative stress is a well-known cause of multiple diseases. The nuclear factor erythroid 2-related factor 2 (Nrf2)-antioxidant response element (ARE) pathway plays a central role in cellular antioxidative responses. In this study, we investigated the effects of novel fatty acid metabolite derivatives of linoleic acid generated by the gut lactic acid bacteria Lactobacillus plantarum on the Nrf2-ARE pathway. 10-Oxo-trans-11-octadecenoic acid (KetoC) protected HepG2 cells from cytotoxicity induced by hydrogen peroxide. KetoC also significantly increased cellular Nrf2 protein levels, ARE-dependent transcription, and the gene expression of antioxidative enzymes such as heme oxygenase-1 (HO-1), glutamate-cysteine ligase modifier subunit (GCLM), and NAD(P)H:quinone oxidoreductasemore » 1 (NQO1) in HepG2 cells. Additionally, a single oral dose administration of KetoC also increased antioxidative gene expression and protein levels of Nrf2 and HO-1 in mouse organs. Since other fatty acid metabolites and linoleic acid did not affect cellular antioxidative responses, the cytoprotective effect of KetoC may be because of its α,β-unsaturated carbonyl moiety. Collectively, our data suggested that KetoC activated the Nrf2-ARE pathway to enhance cellular antioxidative responses in vitro and in vivo, which further suggests that KetoC may prevent multiple diseases induced by oxidative stress. - Highlights: • We evaluated the effect of modified fatty acids generated by Lactobacillus plantarum. • 10-Oxo-trans-11-ocatadecenoic acid (KetoC) protected cells from oxidative stress. • KetoC activated the Nrf2-ARE pathway to promote antioxidative gene expression. • KetoC promoted the expression of antioxidative enzymes in mice organs. • The cytoprotective effect of KetoC was because of α,β-unsaturated carbonyl moiety.« less

Biology Based Lung Cancer Model for Chronic Low Radon Exposures

NASA Astrophysics Data System (ADS)

TruÅ£ǎ-Popa, Lucia-Adina; Hofmann, Werner; Fakir, Hatim; Cosma, Constantin

2008-08-01

Low dose effects of alpha particles at the tissue level are characterized by the interaction of single alpha particles, affecting only a small fraction of the cells within that tissue. Alpha particle intersections of bronchial target cells during a given exposure period were simulated by an initiation-promotion model, formulated in terms of cellular hits within the cycle time of the cell (dose-rate) and then integrated over the whole exposure period (dose). For a given average number of cellular hits during the lifetime of bronchial cells, the actual number of single and multiple hits was selected from a Poisson distribution. While oncogenic transformation is interpreted as the primary initiation step, stimulated mitosis by killing adjacent cells is assumed to be the primary radiological promotion event. Analytical initiation and promotion functions were derived from experimental in vitro data on oncogenic transformation and cellular survival. To investigate the shape of the lung cancer risk function at chronic, low level exposures in more detail, additional biological factors describing the tissue response and operating specifically at low doses were incorporated into the initiation-promotion model. These mechanisms modifying the initial response at the cellular level were: adaptive response, genomic instability, induction of apoptosis by surrounding cells, and detrimental as well as protective bystander mechanisms. To quantify the effects of these mechanisms as functions of dose, analytical functions were derived from the experimental evidence presently available. Predictions of lung cancer risk, including these mechanisms, exhibit a distinct sublinear dose-response relationship at low exposures, particularly for very low exposure rates.

Cellular basis of morphological variation and temperature-related plasticity in Drosophila melanogaster strains with divergent wing shapes.

PubMed

Torquato, Libéria Souza; Mattos, Daniel; Matta, Bruna Palma; Bitner-Mathé, Blanche Christine

2014-12-01

Organ shape evolves through cross-generational changes in developmental patterns at cellular and/or tissue levels that ultimately alter tissue dimensions and final adult proportions. Here, we investigated the cellular basis of an artificially selected divergence in the outline shape of Drosophila melanogaster wings, by comparing flies with elongated or rounded wing shapes but with remarkably similar wing sizes. We also tested whether cellular plasticity in response to developmental temperature was altered by such selection. Results show that variation in cellular traits is associated with wing shape differences, and that cell number may play an important role in wing shape response to selection. Regarding the effects of developmental temperature, a size-related plastic response was observed, in that flies reared at 16 °C developed larger wings with larger and more numerous cells across all intervein regions relative to flies reared at 25 °C. Nevertheless, no conclusive indication of altered phenotypic plasticity was found between selection strains for any wing or cellular trait. We also described how cell area is distributed across different intervein regions. It follows that cell area tends to decrease along the anterior wing compartment and increase along the posterior one. Remarkably, such pattern was observed not only in the selected strains but also in the natural baseline population, suggesting that it might be canalized during development and was not altered by the intense program of artificial selection for divergent wing shapes.

Platelets Guide Leukocytes to Their Sites of Extravasation

PubMed Central

Puhr-Westerheide, Daniel; Pörnbacher, Michaela; Lauber, Kirsten; Krombach, Fritz; Reichel, Christoph Andreas

2016-01-01

Effective immune responses require the directed migration of leukocytes from the vasculature to the site of injury or infection. How immune cells “find” their site of extravasation remains largely obscure. Here, we identified a previously unrecognized role of platelets as pathfinders guiding leukocytes to their exit points in the microvasculature: upon onset of inflammation, circulating platelets were found to immediately adhere at distinct sites in venular microvessels enabling these cellular blood components to capture neutrophils and, in turn, inflammatory monocytes via CD40-CD40L-dependent interactions. In this cellular crosstalk, ligation of PSGL-1 by P-selectin leads to ERK1/2 MAPK-dependent conformational changes of leukocyte integrins, which promote the successive extravasation of neutrophils and monocytes to the perivascular tissue. Conversely, blockade of this cellular partnership resulted in misguided, inefficient leukocyte responses. Our experimental data uncover a platelet-directed, spatiotemporally organized, multicellular crosstalk that is essential for effective trafficking of leukocytes to the site of inflammation. PMID:27152726

Identification of bovine leukemia virus tax function associated with host cell transcription, signaling, stress response and immune response pathway by microarray-based gene expression analysis

PubMed Central

2012-01-01

Background Bovine leukemia virus (BLV) is associated with enzootic bovine leukosis and is closely related to human T-cell leukemia virus type I. The Tax protein of BLV is a transcriptional activator of viral replication and a key contributor to oncogenic potential. We previously identified interesting mutant forms of Tax with elevated (TaxD247G) or reduced (TaxS240P) transactivation effects on BLV replication and propagation. However, the effects of these mutations on functions other than transcriptional activation are unknown. In this study, to identify genes that play a role in the cascade of signal events regulated by wild-type and mutant Tax proteins, we used a large-scale host cell gene-profiling approach. Results Using a microarray containing approximately 18,400 human mRNA transcripts, we found several alterations after the expression of Tax proteins in genes involved in many cellular functions such as transcription, signal transduction, cell growth, apoptosis, stress response, and immune response, indicating that Tax protein has multiple biological effects on various cellular environments. We also found that TaxD247G strongly regulated more genes involved in transcription, signal transduction, and cell growth functions, contrary to TaxS240P, which regulated fewer genes. In addition, the expression of genes related to stress response significantly increased in the presence of TaxS240P as compared to wild-type Tax and TaxD247G. By contrast, the largest group of downregulated genes was related to immune response, and the majority of these genes belonged to the interferon family. However, no significant difference in the expression level of downregulated genes was observed among the Tax proteins. Finally, the expression of important cellular factors obtained from the human microarray results were validated at the RNA and protein levels by real-time quantitative reverse transcription-polymerase chain reaction and western blotting, respectively, after transfecting Tax proteins into bovine cells and human HeLa cells. Conclusion A comparative analysis of wild-type and mutant Tax proteins indicates that Tax protein exerts a significant impact on cellular functions as diverse as transcription, signal transduction, cell growth, stress response and immune response. Importantly, our study is the first report that shows the extent to which BLV Tax regulates the innate immune response. PMID:22455445

Molecular Mechanism for Cellular Response to β-Escin and Its Therapeutic Implications.

PubMed

Domanski, Dominik; Zegrocka-Stendel, Oliwia; Perzanowska, Anna; Dutkiewicz, Malgorzata; Kowalewska, Magdalena; Grabowska, Iwona; Maciejko, Dorota; Fogtman, Anna; Dadlez, Michal; Koziak, Katarzyna

2016-01-01

β-escin is a mixture of triterpene saponins isolated from the horse chestnut seeds (Aesculus hippocastanum L.). The anti-edematous, anti-inflammatory and venotonic properties of β-escin have been the most extensively clinically investigated effects of this plant-based drug and randomized controlled trials have proved the efficacy of β-escin for the treatment of chronic venous insufficiency. However, despite the clinical recognition of the drug its pharmacological mechanism of action still remains largely elusive. To determine the cellular and molecular basis for the therapeutic effectiveness of β-escin we performed discovery and targeted proteomic analyses and in vitro evaluation of cellular and molecular responses in human endothelial cells under inflammatory conditions. Our results demonstrate that in endothelial cells β-escin potently induces cholesterol synthesis which is rapidly followed with marked fall in actin cytoskeleton integrity. The concomitant changes in cell functioning result in a significantly diminished responses to TNF-α stimulation. These include reduced migration, alleviated endothelial monolayer permeability, and inhibition of NFκB signal transduction leading to down-expression of TNF-α-induced effector proteins. Moreover, the study provides evidence for novel therapeutic potential of β-escin beyond the current vascular indications.

Molecular Mechanism for Cellular Response to β-Escin and Its Therapeutic Implications

PubMed Central

Perzanowska, Anna; Dutkiewicz, Malgorzata; Kowalewska, Magdalena; Grabowska, Iwona; Maciejko, Dorota; Fogtman, Anna; Dadlez, Michal; Koziak, Katarzyna

2016-01-01

β-escin is a mixture of triterpene saponins isolated from the horse chestnut seeds (Aesculus hippocastanum L.). The anti-edematous, anti-inflammatory and venotonic properties of β-escin have been the most extensively clinically investigated effects of this plant-based drug and randomized controlled trials have proved the efficacy of β-escin for the treatment of chronic venous insufficiency. However, despite the clinical recognition of the drug its pharmacological mechanism of action still remains largely elusive. To determine the cellular and molecular basis for the therapeutic effectiveness of β-escin we performed discovery and targeted proteomic analyses and in vitro evaluation of cellular and molecular responses in human endothelial cells under inflammatory conditions. Our results demonstrate that in endothelial cells β-escin potently induces cholesterol synthesis which is rapidly followed with marked fall in actin cytoskeleton integrity. The concomitant changes in cell functioning result in a significantly diminished responses to TNF-α stimulation. These include reduced migration, alleviated endothelial monolayer permeability, and inhibition of NFκB signal transduction leading to down-expression of TNF-α—induced effector proteins. Moreover, the study provides evidence for novel therapeutic potential of β-escin beyond the current vascular indications. PMID:27727329

Activation of the stress proteome as a mechanism for small molecule therapeutics.

PubMed

Brose, Rebecca Deering; Shin, Gloria; McGuinness, Martina C; Schneidereith, Tonya; Purvis, Shirley; Dong, Gao X; Keefer, Jeffrey; Spencer, Forrest; Smith, Kirby D

2012-10-01

Various small molecule pharmacologic agents with different known functions produce similar outcomes in diverse Mendelian and complex disorders, suggesting that they may induce common cellular effects. These molecules include histone deacetylase inhibitors, 4-phenylbutyrate (4PBA) and trichostatin A, and two small molecules without direct histone deacetylase inhibitor activity, hydroxyurea (HU) and sulforaphane. In some cases, the therapeutic effects of histone deacetylase inhibitors have been attributed to an increase in expression of genes related to the disease-causing gene. However, here we show that the pharmacological induction of mitochondrial biogenesis was necessary for the potentially therapeutic effects of 4PBA or HU in two distinct disease models, X-linked adrenoleukodystrophy and sickle cell disease. We hypothesized that a common cellular response to these four molecules is induction of mitochondrial biogenesis and peroxisome proliferation and activation of the stress proteome, or adaptive cell survival response. Treatment of human fibroblasts with these four agents induced mitochondrial and peroxisomal biogenesis as monitored by flow cytometry, immunofluorescence and/or western analyses. In treated normal human fibroblasts, all four agents induced the adaptive cell survival response: heat shock, unfolded protein, autophagic and antioxidant responses and the c-jun N-terminal kinase pathway, at the transcriptional and translational levels. Thus, activation of the evolutionarily conserved stress proteome and mitochondrial biogenesis may be a common cellular response to such small molecule therapy and a common basis of therapeutic action in various diseases. Modulation of this novel therapeutic target could broaden the range of treatable diseases without directly targeting the causative genetic abnormalities.

Activation of the stress proteome as a mechanism for small molecule therapeutics

PubMed Central

Brose, Rebecca Deering; Shin, Gloria; McGuinness, Martina C.; Schneidereith, Tonya; Purvis, Shirley; Dong, Gao X.; Keefer, Jeffrey; Spencer, Forrest; Smith, Kirby D.

2012-01-01

Various small molecule pharmacologic agents with different known functions produce similar outcomes in diverse Mendelian and complex disorders, suggesting that they may induce common cellular effects. These molecules include histone deacetylase inhibitors, 4-phenylbutyrate (4PBA) and trichostatin A, and two small molecules without direct histone deacetylase inhibitor activity, hydroxyurea (HU) and sulforaphane. In some cases, the therapeutic effects of histone deacetylase inhibitors have been attributed to an increase in expression of genes related to the disease-causing gene. However, here we show that the pharmacological induction of mitochondrial biogenesis was necessary for the potentially therapeutic effects of 4PBA or HU in two distinct disease models, X-linked adrenoleukodystrophy and sickle cell disease. We hypothesized that a common cellular response to these four molecules is induction of mitochondrial biogenesis and peroxisome proliferation and activation of the stress proteome, or adaptive cell survival response. Treatment of human fibroblasts with these four agents induced mitochondrial and peroxisomal biogenesis as monitored by flow cytometry, immunofluorescence and/or western analyses. In treated normal human fibroblasts, all four agents induced the adaptive cell survival response: heat shock, unfolded protein, autophagic and antioxidant responses and the c-jun N-terminal kinase pathway, at the transcriptional and translational levels. Thus, activation of the evolutionarily conserved stress proteome and mitochondrial biogenesis may be a common cellular response to such small molecule therapy and a common basis of therapeutic action in various diseases. Modulation of this novel therapeutic target could broaden the range of treatable diseases without directly targeting the causative genetic abnormalities. PMID:22752410

Priming T-cell responses with recombinant measles vaccine vector in a heterologous prime-boost setting in non-human primates.

PubMed

Bolton, Diane L; Santra, Sampa; Swett-Tapia, Cindy; Custers, Jerome; Song, Kaimei; Balachandran, Harikrishnan; Mach, Linh; Naim, Hussein; Kozlowski, Pamela A; Lifton, Michelle; Goudsmit, Jaap; Letvin, Norman; Roederer, Mario; Radošević, Katarina

2012-09-07

Licensed live attenuated virus vaccines capable of expressing transgenes from other pathogens have the potential to reduce the number of childhood immunizations by eliciting robust immunity to multiple pathogens simultaneously. Recombinant attenuated measles virus (rMV) derived from the Edmonston Zagreb vaccine strain was engineered to express simian immunodeficiency virus (SIV) Gag protein for the purpose of evaluating the immunogenicity of rMV as a vaccine vector in rhesus macaques. rMV-Gag immunization alone elicited robust measles-specific humoral and cellular responses, but failed to elicit transgene (Gag)-specific immune responses, following aerosol or intratracheal/intramuscular delivery. However, when administered as a priming vaccine to a heterologous boost with recombinant adenovirus serotype 5 expressing the same transgene, rMV-Gag significantly enhanced Gag-specific T lymphocyte responses following rAd5 immunization. Gag-specific humoral responses were not enhanced, however, which may be due to either the transgene or the vector. Cellular response priming by rMV against the transgene was highly effective even when using a suboptimal dose of rAd5 for the boost. These data demonstrate feasibility of using rMV as a priming component of heterologous prime-boost vaccine regimens for pathogens requiring strong cellular responses. Copyright © 2012 Elsevier Ltd. All rights reserved.

The Cellular and Molecular Carcinogenic Effects of Radon Exposure: A Review

PubMed Central

Robertson, Aaron; Allen, James; Laney, Robin; Curnow, Alison

2013-01-01

Radon-222 is a naturally occurring radioactive gas that is responsible for approximately half of the human annual background radiation exposure globally. Chronic exposure to radon and its decay products is estimated to be the second leading cause of lung cancer behind smoking, and links to other forms of neoplasms have been postulated. Ionizing radiation emitted during the radioactive decay of radon and its progeny can induce a variety of cytogenetic effects that can be biologically damaging and result in an increased risk of carcinogenesis. Suggested effects produced as a result of alpha particle exposure from radon include mutations, chromosome aberrations, generation of reactive oxygen species, modification of the cell cycle, up or down regulation of cytokines and the increased production of proteins associated with cell-cycle regulation and carcinogenesis. A number of potential biomarkers of exposure, including translocations at codon 249 of TP53 in addition to HPRT mutations, have been suggested although, in conclusion, the evidence for such hotspots is insufficient. There is also substantial evidence of bystander effects, which may provide complications when calculating risk estimates as a result of exposure, particularly at low doses where cellular responses often appear to deviate from the linear, no-threshold hypothesis. At low doses, effects may also be dependent on cellular conditions as opposed to dose. The cellular and molecular carcinogenic effects of radon exposure have been observed to be both numerous and complex and the elevated chronic exposure of man may therefore pose a significant public health risk that may extend beyond the association with lung carcinogenesis. PMID:23880854

Psychedelics Recruit Multiple Cellular Types and Produce Complex Transcriptional Responses Within the Brain.

PubMed

Martin, David A; Nichols, Charles D

2016-09-01

There has recently been a resurgence of interest in psychedelics, substances that profoundly alter perception and cognition and have recently demonstrated therapeutic efficacy to treat anxiety, depression, and addiction in the clinic. The receptor mechanisms that drive their molecular and behavioral effects involve activation of cortical serotonin 5-HT 2A receptors, but the responses of specific cellular populations remain unknown. Here, we provide evidence that a small subset of 5-HT 2A -expressing excitatory neurons is directly activated by psychedelics and subsequently recruits other select cell types including subpopulations of inhibitory somatostatin and parvalbumin GABAergic interneurons, as well as astrocytes, to produce distinct and regional responses. To gather data regarding the response of specific neuronal populations, we developed methodology for fluorescence-activated cell sorting (FACS) to segregate and enrich specific cellular subtypes in the brain. These methods allow for robust neuronal sorting based on cytoplasmic epitopes followed by downstream nucleic acid analysis, expanding the utility of FACS in neuroscience research. Copyright © 2016 Forschungsgesellschaft für Arbeitsphysiologie und Arbeitschutz e.V. Published by Elsevier B.V. All rights reserved.

Maintenance of cytosolic calcium is crucial to extend l-arginine therapeutic benefits during continuous dosing.

PubMed

Mohan, Srinidi; Harding, Lisa

2016-10-01

The therapeutic benefits associated with short-term l-arginine supplementation are lost during continuous dosing. AMP-activated protein kinase (AMPK) functional modulation has been correlated with l-arginine therapeutic effectiveness, and with tolerance development during continuous supplementation. However, the metabolic link that is responsible for AMPK functional modulation during continuous l-arginine exposure is currently not known. To explore this, we incubated HUVECs for 7 days with 100 μmol/L l-arginine, in the presence or absence of other agents; and monitored their effects for eNOS function, and on tolerance sparing effects (viz, cellular glucose accumulation, and oxidative stress). HUVEC co-incubation with 100 μmol/L l-arginine and ≤1200 mg/mL calcium (Ca 2+ ) for 7 days avoided tolerance development, with an at least 1-fold increase in the eNOS and AMPK functional activity; and an 1-fold increase in overall cellular glucose uptake. The overall cellular cytosolic Ca 2+ was below 200 nmol/L, with no change in cellular glucose and superoxide/peroxynitrite (O 2 •- /ONOO - ) level from control. However, tolerance sparing effects of at least 70% decrease in eNOS and AMPK functional response, with an 1-fold reduction in glucose uptake, and at least 2-fold increase in O 2 •- /ONOO - were observed in cells exposed for 7 days to 100 μmol/L l-arginine at Ca 2+ co-incubation concentration of >1200 mg/mL. The >1200 mg/mL Ca2+ co-incubation condition, also improved the overall cellular Ca 2+ to >200 nmol/L. Similar tolerance response was observed in cells co-treated with 100 μmol/L l-arginine and ≤1200 mg/mL Ca 2+ in the presence of Ca 2+ influx inhibitor (20 μmol/L 1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetra acetic acid), or eNOS activity inhibitor (30 μmol/L l-N G -nitroarginine methyl ester). No tolerance response was seen in cells incubated for 7 days with 100 μmol/L l-arginine and ≤1200 mg/mL Ca 2+ ; even in the presence of the inhibitor for cellular glucose induction (30 μmol/L 5-chloro-2-(n-(2,5-dichlorobenzenesulfonamide))-benzoxazole). The present study thus provides the first definitive evidence that shows the need to maintain cytosolic Ca 2+ within a threshold limit of less than 200 nmol/L to extend l-arginine therapeutic efficacy during continuous dosing, without any potential tolerance development. Copyright © 2016 Elsevier Inc. All rights reserved.

Enhanced early innate and T cell-mediated responses in subjects immunized with Anthrax Vaccine Adsorbed Plus CPG 7909 (AV7909).

PubMed

Minang, Jacob T; Inglefield, Jon R; Harris, Andrea M; Lathey, Janet L; Alleva, David G; Sweeney, Diane L; Hopkins, Robert J; Lacy, Michael J; Bernton, Edward W

2014-11-28

NuThrax™ (Anthrax Vaccine Adsorbed with CPG 7909 Adjuvant) (AV7909) is in development. Samples obtained in a phase Ib clinical trial were tested to confirm biomarkers of innate immunity and evaluate effects of CPG 7909 (PF-03512676) on adaptive immunity. Subjects received two intramuscular doses of commercial BioThrax(®) (Anthrax Vaccine Adsorbed, AVA), or two intramuscular doses of one of four formulations of AV7909. IP-10, IL-6, and C-reactive protein (CRP) levels were elevated 24-48 h after administration of AV7909 formulations, returning to baseline by Day 7. AVA (no CPG 7909) resulted in elevated IL-6 and CRP, but not IP-10. Another marker of CpG, transiently decreased absolute lymphocyte counts (ALCs), correlated with transiently increased IP-10. Cellular recall responses to anthrax protective antigen (PA) or PA peptides were assessed by IFN-γ ELISpot assay performed on cryopreserved PBMCs obtained from subjects prior to immunization and 7 days following the second immunization (study day 21). One-half of subjects that received AV7909 with low-dose (0.25mg/dose) CPG 7909 possessed positive Day 21 T cell responses to PA. In contrast, positive T cell responses occurred at an 11% average rate (1/9) for AVA-treated subjects. Differences in cellular responses due to dose level of CPG 7909 were not associated with differences in humoral anti-PA IgG responses, which were elevated for recipients of AV7909 compared to recipients of AVA. Serum markers at 24 or 48 h (i.e. % ALC decrease, or increase in IL-6, IP-10, or CRP) correlated with the humoral (antibody) responses 1 month later, but did not correlate with cellular ELISpot responses. In summary, biomarkers of early responses to CPG 7909 were confirmed, and adding a CpG adjuvant to a vaccine administered twice resulted in increased T cell effects relative to vaccine alone. Changes in early biomarkers correlated with subsequent adaptive humoral immunity but not cellular immunity. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Thickness sensing of hMSCs on collagen gel directs stem cell fate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leong, Wen Shing; Tay, Chor Yong; Yu, Haiyang

Research highlights: {yields} hMSCs appeared to sense thin collagen gel (130 {mu}m) with higher effective modulus as compared to thick gel (1440 {mu}m). {yields} Control of collagen gel thickness can modulate cellular behavior, even stem cell fate (neuronal vs. Quiescent). {yields} Distinct cellular behavior of hMSCs on thin and thick collagen gel suggests long range interaction of hMSCs with collagen gel. -- Abstract: Mechanically compliant substrate provides crucial biomechanical cues for multipotent stem cells to regulate cellular fates such as differentiation, proliferation and maintenance of their phenotype. Effective modulus of which cells sense is not only determined by intrinsic mechanicalmore » properties of the substrate, but also the thickness of substrate. From our study, it was found that interference from underlying rigid support at hundreds of microns away could induce significant cellular response. Human mesenchymal stem cells (hMSCs) were cultured on compliant biological gel, collagen type I, of different thickness but identical ECM composition and local stiffness. The cells sensed the thin gel (130 {mu}m) as having a higher effective modulus than the thick gel (1440 {mu}m) and this was reflected in their changes in morphology, actin fibers structure, proliferation and tissue specific gene expression. Commitment into neuronal lineage was observed on the thin gel only. Conversely, the thick gel (1440 {mu}m) was found to act like a substrate with lower effective modulus that inhibited actin fiber polymerization. Stem cells on the thick substrate did not express tissue specific genes and remained at their quiescent state. This study highlighted the need to consider not only the local modulus but also the thickness of biopolymer gel coating during modulation of cellular responses.« less

Hemagglutinating virus of Japan envelope (HVJ-E) can enhance the immune responses of swine immunized with killed PRRSV vaccine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dai, Zhihong; China Institute of Veterinary Drug Control, Beijing 100081; Zhang, Quan

Highlights: Black-Right-Pointing-Pointer We investigated the immunoadjuvant effects of HVJ-E on killed PRRSV vaccine. Black-Right-Pointing-Pointer HVJ-E enhanced the humoral and cellular responses of the piglets to PRRSV. Black-Right-Pointing-Pointer It is suggested that HVJ-E could be developed as a new-type adjuvant for mammals. -- Abstract: Porcine reproductive and respiratory syndrome virus (PRRSV) is an economically detrimental pig pathogen that causes significant losses for the pig industry. The immunostimulatory effects of hemagglutinating virus of Japan envelope (HVJ-E) in cancer therapy and the adjuvant efficacy of HVJ-E have been previously evaluated. The objective of this study was to investigate the adjuvant effects of HVJ-Emore » on immunization with killed PRRSV vaccine, and to evaluate the protective effects of this immunization strategy against virulent PRRSV infection in piglets. Next, the PRRSV-specific antibody response, lymphocyte proliferation, PRRSV-specific IL-2, IL-10 and IFN-{gamma} production, and the overall protection efficacy were evaluated to assess the immune responses of the piglets. The results showed that the piglets inoculated simultaneously with killed PRRSV vaccine and HVJ-E had a significantly stronger immune response than those inoculated with killed PRRSV vaccine alone. Our results suggest that HVJ-E could be employed as an effective adjuvant to enhance the humoral and cellular responses of piglets to PRRSV.« less

Carnauba wax nanoparticles enhance strong systemic and mucosal cellular and humoral immune responses to HIV-gp140 antigen

PubMed Central

Arias, Mauricio A.; Loxley, Andrew; Eatmon, Christy; Van Roey, Griet; Fairhurst, David; Mitchnick, Mark; Dash, Philip; Cole, Tom; Wegmann, Frank; Sattentau, Quentin; Shattock, Robin

2011-01-01

Induction of humoral responses to HIV at mucosal compartments without inflammation is important for vaccine design. We developed charged wax nanoparticles that efficiently adsorb protein antigens and are internalized by DC in the absence of inflammation. HIV-gp140-adsorbed nanoparticles induced stronger in vitro T-cell proliferation responses than antigen alone. Such responses were greatly enhanced when antigen was co-adsorbed with TLR ligands. Immunogenicity studies in mice showed that intradermal vaccination with HIV-gp140 antigen-adsorbed nanoparticles induced high levels of specific IgG. Importantly, intranasal immunization with HIV-gp140-adsorbed nanoparticles greatly enhanced serum and vaginal IgG and IgA responses. Our results show that HIV-gp140-carrying wax nanoparticles can induce strong cellular/humoral immune responses without inflammation and may be of potential use as effective mucosal adjuvants for HIV vaccine candidates. PMID:21145913

Carnauba wax nanoparticles enhance strong systemic and mucosal cellular and humoral immune responses to HIV-gp140 antigen.

PubMed

Arias, Mauricio A; Loxley, Andrew; Eatmon, Christy; Van Roey, Griet; Fairhurst, David; Mitchnick, Mark; Dash, Philip; Cole, Tom; Wegmann, Frank; Sattentau, Quentin; Shattock, Robin

2011-02-01

Induction of humoral responses to HIV at mucosal compartments without inflammation is important for vaccine design. We developed charged wax nanoparticles that efficiently adsorb protein antigens and are internalized by DC in the absence of inflammation. HIV-gp140-adsorbed nanoparticles induced stronger in vitro T-cell proliferation responses than antigen alone. Such responses were greatly enhanced when antigen was co-adsorbed with TLR ligands. Immunogenicity studies in mice showed that intradermal vaccination with HIV-gp140 antigen-adsorbed nanoparticles induced high levels of specific IgG. Importantly, intranasal immunization with HIV-gp140-adsorbed nanoparticles greatly enhanced serum and vaginal IgG and IgA responses. Our results show that HIV-gp140-carrying wax nanoparticles can induce strong cellular/humoral immune responses without inflammation and may be of potential use as effective mucosal adjuvants for HIV vaccine candidates. Copyright © 2010 Elsevier Ltd. All rights reserved.

Intraspecific variation in cellular and biochemical heat response strategies of Mediterranean Xeropicta derbentina [Pulmonata, Hygromiidae].

PubMed

Troschinski, Sandra; Di Lellis, Maddalena A; Sereda, Sergej; Hauffe, Torsten; Wilke, Thomas; Triebskorn, Rita; Köhler, Heinz-R

2014-01-01

Dry and hot environments challenge the survival of terrestrial snails. To minimize overheating and desiccation, physiological and biochemical adaptations are of high importance for these animals. In the present study, seven populations of the Mediterranean land snail species Xeropicta derbentina were sampled from their natural habitat in order to investigate the intraspecific variation of cellular and biochemical mechanisms, which are assigned to contribute to heat resistance. Furthermore, we tested whether genetic parameters are correlated with these physiological heat stress response patterns. Specimens of each population were individually exposed to elevated temperatures (25 to 52°C) for 8 h in the laboratory. After exposure, the health condition of the snails' hepatopancreas was examined by means of qualitative description and semi-quantitative assessment of histopathological effects. In addition, the heat-shock protein 70 level (Hsp70) was determined. Generally, calcium cells of the hepatopancreas were more heat resistant than digestive cells - this phenomenon was associated with elevated Hsp70 levels at 40°C.We observed considerable variation in the snails' heat response strategy: Individuals from three populations invested much energy in producing a highly elevated Hsp70 level, whereas three other populations invested energy in moderate stress protein levels - both strategies were in association with cellular functionality. Furthermore, one population kept cellular condition stable despite a low Hsp70 level until 40°C exposure, whereas prominent cellular reactions were observed above this thermal limit. Genetic diversity (mitochondrial cytochrome c oxidase subunit I gene) within populations was low. Nevertheless, when using genetic indices as explanatory variables in a multivariate regression tree (MRT) analysis, population structure explained mean differences in cellular and biochemical heat stress responses, especially in the group exposed to 40°C. Our study showed that, even in similar habitats within a close range, populations of the same species use different stress response strategies that all rendered survival possible.

Intraspecific Variation in Cellular and Biochemical Heat Response Strategies of Mediterranean Xeropicta derbentina [Pulmonata, Hygromiidae

PubMed Central

Troschinski, Sandra; Di Lellis, Maddalena A.; Sereda, Sergej; Hauffe, Torsten; Wilke, Thomas; Triebskorn, Rita; Köhler, Heinz-R.

2014-01-01

Dry and hot environments challenge the survival of terrestrial snails. To minimize overheating and desiccation, physiological and biochemical adaptations are of high importance for these animals. In the present study, seven populations of the Mediterranean land snail species Xeropicta derbentina were sampled from their natural habitat in order to investigate the intraspecific variation of cellular and biochemical mechanisms, which are assigned to contribute to heat resistance. Furthermore, we tested whether genetic parameters are correlated with these physiological heat stress response patterns. Specimens of each population were individually exposed to elevated temperatures (25 to 52°C) for 8 h in the laboratory. After exposure, the health condition of the snails' hepatopancreas was examined by means of qualitative description and semi-quantitative assessment of histopathological effects. In addition, the heat-shock protein 70 level (Hsp70) was determined. Generally, calcium cells of the hepatopancreas were more heat resistant than digestive cells - this phenomenon was associated with elevated Hsp70 levels at 40°C.We observed considerable variation in the snails' heat response strategy: Individuals from three populations invested much energy in producing a highly elevated Hsp70 level, whereas three other populations invested energy in moderate stress protein levels - both strategies were in association with cellular functionality. Furthermore, one population kept cellular condition stable despite a low Hsp70 level until 40°C exposure, whereas prominent cellular reactions were observed above this thermal limit. Genetic diversity (mitochondrial cytochrome c oxidase subunit I gene) within populations was low. Nevertheless, when using genetic indices as explanatory variables in a multivariate regression tree (MRT) analysis, population structure explained mean differences in cellular and biochemical heat stress responses, especially in the group exposed to 40°C. Our study showed that, even in similar habitats within a close range, populations of the same species use different stress response strategies that all rendered survival possible. PMID:24475158

AMP-activated protein kinase reduces inflammatory responses and cellular senescence in pulmonary emphysema.

PubMed

Cheng, Xiao-Yu; Li, Yang-Yang; Huang, Cheng; Li, Jun; Yao, Hong-Wei

2017-04-04

Current drug therapy fails to reduce lung destruction of chronic obstructive pulmonary disease (COPD). AMP-activated protein kinase (AMPK) has emerged as an important integrator of signals that control energy balance and lipid metabolism. However, there are no studies regarding the role of AMPK in reducing inflammatory responses and cellular senescence during the development of emphysema. Therefore, we hypothesize that AMPK reduces inflammatroy responses, senescence, and lung injury. To test this hypothesis, human bronchial epithelial cells (BEAS-2B) and small airway epithelial cells (SAECs) were treated with cigarette smoke extract (CSE) in the presence of a specific AMPK activator (AICAR, 1 mM) and inhibitor (Compound C, 5 μM). Elastase injection was performed to induce mouse emphysema, and these mice were treated with a specific AMPK activator metformin as well as Compound C. AICAR reduced, whereas Compound C increased CSE-induced increase in IL-8 and IL-6 release and expression of genes involved in cellular senescence. Knockdown of AMPKα1/α2 increased expression of pro-senescent genes (e.g., p16, p21, and p66shc) in BEAS-2B cells. Prophylactic administration of an AMPK activator metformin (50 and 250 mg/kg) reduced while Compound C (4 and 20 mg/kg) aggravated elastase-induced airspace enlargement, inflammatory responses and cellular senescence in mice. This is in agreement with therapeutic effect of metformin (50 mg/kg) on airspace enlargement. Furthermore, metformin prophylactically protected against but Compound C further reduced mitochondrial proteins SOD2 and SIRT3 in emphysematous lungs. In conclusion, AMPK reduces abnormal inflammatory responses and cellular senescence, which implicates as a potential therapeutic target for COPD/emphysema.

High hydrostatic pressure and the cell membrane: stress response of Saccharomyces cerevisiae.

PubMed

Bravim, Fernanda; de Freitas, Jéssica M; Fernandes, A Alberto R; Fernandes, Patricia M B

2010-02-01

The brewing and baking yeast Saccharomyces cerevisiae is a useful eukaryotic model of stress response systems whose study could lead to the understanding of stress response mechanisms in other organisms. High hydrostatic pressure (HHP) exerts broad effects upon yeast cells, interfering with cell membranes, cellular architecture, and the processes of polymerization and denaturation of proteins. In this review, we focus on the effect of HHP on the S. cerevisiae cell membrane and describe the main signaling pathways involved in the pressure response.

Light-dependent governance of cell shape dimensions in cyanobacteria.

PubMed

Montgomery, Beronda L

2015-01-01

The regulation of cellular dimension is important for the function and survival of cells. Cellular dimensions, such as size and shape, are regulated throughout the life cycle of bacteria and can be adapted in response to environmental changes to fine-tune cellular fitness. Cell size and shape are generally coordinated with cell growth and division. Cytoskeletal regulation of cell shape and cell wall biosynthesis and/or deposition occurs in a range of organisms. Photosynthetic organisms, such as cyanobacteria, particularly exhibit light-dependent regulation of morphogenes and generation of reactive oxygen species and other signals that can impact cellular dimensions. Environmental signals initiate adjustments of cellular dimensions, which may be vitally important for optimizing resource acquisition and utilization or for coupling the cellular dimensions with the regulation of subcellular organization to maintain optimal metabolism. Although the involvement of cytoskeletal components in the regulation of cell shape is widely accepted, the signaling factors that regulate cytoskeletal and other distinct components involved in cell shape control, particularly in response to changes in external light cues, remain to be fully elucidated. In this review, factors impacting the inter-coordination of growth and division, the relationship between the regulation of cellular dimensions and central carbon metabolism, and consideration of the effects of specific environment signals, primarily light, on cell dimensions in cyanobacteria will be discussed. Current knowledge about the molecular bases of the light-dependent regulation of cellular dimensions and cell shape in cyanobacteria will be highlighted.

Effect of the bacillus of Calmette-Guérin, Propionibacter acnes and avridine as immunomodulators in antirabies vaccination of mice using the Fuenzalida-Palacios mouse brain vaccine.

PubMed

Megid, J; Peraçolli, M T; Curi, P R; Zanetti, C R; Cabrera, W H; Vassao, R; Ito, F H

1999-05-14

Using the laboratory mice, Fuenzalida-Palacios mouse brain human rabies vaccine was administered in groups of animals previously inoculated with rabies virus and then submitted to treatments with the immunomodulators onco-BCG, avridine and Propionibacterium acnes. Humoral and cellular immune responses were evaluated through the macrophage inhibition factor (MIF), intra-pad inoculation (IPI) and serum neutralization (SN) tests and by the detection of gamma-interferon (IFN-gamma). The IPI test was not effective in detecting the response of delayed-type hypersensitivity, contrary to MIF, which showed the immune cellular response. Higher levels of IFN-gamma were observed in the groups of mice vaccinated and treated with avridine and P. acnes. Although immunomodulating activities have been detected, the use of adjuvants with the Fuenzalida-Palacios type vaccine in mice did not reveal any encouraging results.

Elevated hypothalamic TCPTP in obesity contributes to cellular leptin resistance

PubMed Central

Loh, Kim; Fukushima, Atsushi; Zhang, Xinmei; Galic, Sandra; Briggs, Dana; Enriori, Pablo J.; Simonds, Stephanie; Wiede, Florian; Reichenbach, Alexander; Hauser, Christine; Sims, Natalie A.; Bence, Kendra K.; Zhang, Sheng; Zhang, Zhong-Yin; Kahn, Barbara B.; Neel, Benjamin G.; Andrews, Zane B.; Cowley, Michael A.; Tiganis, Tony

2011-01-01

SUMMARY In obesity, anorectic responses to leptin are diminished, giving rise to the concept of ‘leptin resistance’. Increased expression of protein tyrosine phosphatase 1B (PTP1B) has been associated with the attenuation of leptin signaling and development of cellular leptin resistance. Here we report that hypothalamic levels of the tyrosine phosphatase TCPTP are also elevated in obesity to attenuate the leptin response. We show that mice that lack TCPTP in neuronal cells have enhanced leptin sensitivity and are resistant to high fat diet-induced weight gain and the development of leptin resistance. Also, intracerebroventricular administration of a TCPTP inhibitor enhances leptin signaling and responses in mice. Moreover, the combined deletion of TCPTP and PTP1B in neuronal cells has additive effects in the prevention of diet-induced obesity. Our results identify TCPTP as a critical negative regulator of hypothalamic leptin signaling and causally link elevated TCPTP to the development of cellular leptin resistance in obesity. PMID:22000926

Vitamin K3 suppressed inflammatory and immune responses in a redox-dependent manner.

PubMed

Checker, Rahul; Sharma, Deepak; Sandur, Santosh K; Khan, Nazir M; Patwardhan, Raghavendra S; Kohli, Vineet; Sainis, Krishna B

2011-08-01

Recent investigations suggest that cellular redox status may play a key role in the regulation of several immune functions. Treatment of lymphocytes with vitamin K3 (menadione) resulted in a significant decrease in cellular GSH/GSSG ratio and concomitant increase in the ROS levels. It also suppressed Concanavalin A (Con A)-induced proliferation and cytokine production in lymphocytes and CD4 + T cells in vitro. Immunosuppressive effects of menadione were abrogated only by thiol containing antioxidants. Mass spectrometric analysis showed that menadione directly interacted with thiol antioxidant GSH. Menadione completely suppressed Con A-induced activation of ERK, JNK and NF-κB in lymphocytes. It also significantly decreased the homeostasis driven proliferation of syngeneic CD4 + T cells. Further, menadione significantly delayed graft-vs-host disease morbidity and mortality in mice. Menadione suppressed phytohemagglutinin-induced cytokine production in human peripheral blood mononuclear cells. These results reveal that cellular redox perturbation by menadione is responsible for significant suppression of lymphocyte responses.

Cannabinoids and Viral Infections

PubMed Central

Reiss, Carol Shoshkes

2010-01-01

Exogenous cannabinoids or receptor antagonists may influence many cellular and systemic host responses. The anti-inflammatory activity of cannabinoids may compromise host inflammatory responses to acute viral infections, but may be beneficial in persistent infections. In neurons, where innate antiviral/pro-resolution responses include the activation of NOS-1, inhibition of Ca2+ activity by cannabinoids, increased viral replication and disease. This review examines the effect(s) of cannabinoids and their antagonists in viral infections. PMID:20634917

Differential cellular responses in healthy mice and in mice with established airway inflammation when exposed to hematite nanoparticles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gustafsson, Åsa, E-mail: asa.gustafsson@foi.se; Dept of Public Health and Clinical Medicine, Umeå University; Bergström, Ulrika

The aim of this study was to investigate the inflammatory and immunological responses in airways and lung-draining lymph nodes (LDLNs), following lung exposure to iron oxide (hematite) nanoparticles (NPs). The responses to the hematite NPs were evaluated in both healthy non-sensitized mice, and in sensitized mice with an established allergic airway disease. The mice were exposed intratracheally to either hematite NPs or to vehicle (PBS) and the cellular responses were evaluated on days 1, 2, and 7, post-exposure. Exposure to hematite NPs increased the numbers of neutrophils, eosinophils, and lymphocytes in the airways of non-sensitized mice on days 1 andmore » 2 post-exposure; at these time points the number of lymphocytes was also elevated in the LDLNs. In contrast, exposing sensitized mice to hematite NPs induced a rapid and unspecific cellular reduction in the alveolar space on day 1 post-exposure; a similar decrease of lymphocytes was also observed in the LDLN. The results indicate that cells in the airways and in the LDLN of individuals with established airway inflammation undergo cell death when exposed to hematite NPs. A possible explanation for this toxic response is the extensive generation of reactive oxygen species (ROS) in the pro-oxidative environment of inflamed airways. This study demonstrates how sensitized and non-sensitized mice respond differently to hematite NP exposure, and it highlights the importance of including individuals with respiratory disorders when evaluating health effects of inhaled nanomaterials. - Highlights: • Hematite NPs induce differential responses in airways of healthy and allergic mice. • Hematite induced an airway inflammation in healthy mice. • Hematite induced cellular reduction in the alveolus and lymph nodes of allergic mice. • Cell death is possible due to extensive pro-oxidative environment in allergic mice. • It is important to include sensitive individuals when valuing health effects of NPs.« less

Response of cellular stoichiometry and phosphorus storage of the cyanobacteria Aphanizomenon flos-aquae to small-scale turbulence

NASA Astrophysics Data System (ADS)

Li, Zhe; Xiao, Yan; Yang, Jixiang; Li, Chao; Gao, Xia; Guo, Jinsong

2017-11-01

Turbulent mixing, in particular on a small scale, affects the growth of microalgae by changing diffusive sublayers and regulating nutrient fluxes of cells. We tested the nutrient flux hypothesis by evaluating the cellular stoichiometry and phosphorus storage of microalgae under different turbulent mixing conditions. Aphanizomenon flos-aquae were cultivated in different stirring batch reactors with turbulent dissipation rates ranging from 0.001 51 m2/s3 to 0.050 58 m2/s3, the latter being the highest range observed in natural aquatic systems. Samples were taken in the exponential growth phase and compared with samples taken when the reactor was completely stagnant. Results indicate that, within a certain range, turbulent mixing stimulates the growth of A. flos-aquae. An inhibitory effect on growth rate was observed at the higher range. Photosynthesis activity, in terms of maximum effective quantum yield of PSII (the ratio of F v/ F m) and cellular chlorophyll a, did not change significantly in response to turbulence. However, Chl a/C mass ratio and C/N molar ratio, showed a unimodal response under a gradient of turbulent mixing, similar to growth rate. Moreover, we found that increases in turbulent mixing might stimulate respiration rates, which might lead to the use of polyphosphate for the synthesis of cellular constituents. More research is required to test and verify the hypothesis that turbulent mixing changes the diffusive sublayer, regulating the nutrient flux of cells.

Cellular and laminar expression of Dab-1 during the postnatal critical period in cat visual cortex and the effects of dark rearing.

PubMed

Kiser, Paul J; Liu, Zijing; Wilt, Steven D; Mower, George D

2011-04-06

This study describes postnatal critical period changes in cellular and laminar expression of Dab-1, a gene shown to play a role in controlling neuronal positioning during embryonic brain development, in cat visual cortex and the effects of dark rearing (DR). At 1week, there is dense cellular staining which is uniform across cortical layers and very light neuropil staining. At the peak of the critical period (5weeks), dense cell staining is largely restricted to large pyramidal cells of deep layer III and layer V, there is faint cell body staining throughout all cortical layers, neuropil staining is markedly increased and uniform in layers III to VI. This dramatic change in laminar and cellular labeling is independent of visual input, since immunostaining is similar in 5-week DR cats. By 10weeks, the mature laminar and cellular staining pattern is established and the major subsequent change is a further reduction in the density of cellular staining in all cortical layers. Neuropil staining is pronounced and uniform across cortical layers. These developmental changes are altered by DR. Quantification by cell counts indicated that age and DR interact such that differences in cellular expression are opposite in direction between 5- and 20-week-old cats. This bidirectional regulation of cellular expression is the same in all cortical laminae. The bidirectional regulation of cellular expression matches the effects of age and DR on physiological plasticity during the critical period as assessed by ocular dominance shifts in response to monocular deprivation. Copyright © 2011 Elsevier B.V. All rights reserved.

Genetic variation in the cellular response of Daphnia magna (Crustacea: Cladocera) to its bacterial parasite.

PubMed

Auld, Stuart K J R; Scholefield, Jennifer A; Little, Tom J

2010-11-07

Linking measures of immune function with infection, and ultimately, host and parasite fitness is a major goal in the field of ecological immunology. In this study, we tested for the presence and timing of a cellular immune response in the crustacean Daphnia magna following exposure to its sterilizing endoparasite Pasteuria ramosa. We found that D. magna possesses two cell types circulating in the haemolymph: a spherical one, which we call a granulocyte and an irregular-shaped amoeboid cell first described by Metchnikoff over 125 years ago. Daphnia magna mounts a strong cellular response (of the amoeboid cells) just a few hours after parasite exposure. We further tested for, and found, considerable genetic variation for the magnitude of this cellular response. These data fostered a heuristic model of resistance in this naturally coevolving host-parasite interaction. Specifically, the strongest cellular responses were found in the most susceptible hosts, indicating resistance is not always borne from a response that destroys invading parasites, but rather stems from mechanisms that prevent their initial entry. Thus, D. magna may have a two-stage defence--a genetically determined barrier to parasite establishment and a cellular response once establishment has begun.

Genetic variation in the cellular response of Daphnia magna (Crustacea: Cladocera) to its bacterial parasite

PubMed Central

Auld, Stuart K. J. R.; Scholefield, Jennifer A.; Little, Tom J.

2010-01-01

Linking measures of immune function with infection, and ultimately, host and parasite fitness is a major goal in the field of ecological immunology. In this study, we tested for the presence and timing of a cellular immune response in the crustacean Daphnia magna following exposure to its sterilizing endoparasite Pasteuria ramosa. We found that D. magna possesses two cell types circulating in the haemolymph: a spherical one, which we call a granulocyte and an irregular-shaped amoeboid cell first described by Metchnikoff over 125 years ago. Daphnia magna mounts a strong cellular response (of the amoeboid cells) just a few hours after parasite exposure. We further tested for, and found, considerable genetic variation for the magnitude of this cellular response. These data fostered a heuristic model of resistance in this naturally coevolving host–parasite interaction. Specifically, the strongest cellular responses were found in the most susceptible hosts, indicating resistance is not always borne from a response that destroys invading parasites, but rather stems from mechanisms that prevent their initial entry. Thus, D. magna may have a two-stage defence—a genetically determined barrier to parasite establishment and a cellular response once establishment has begun. PMID:20534618

Effects of temperature and cellular interactions on the mechanics and morphology of human cancer cells investigated by atomic force microscopy.

PubMed

Li, Mi; Liu, LianQing; Xi, Ning; Wang, YueChao; Xiao, XiuBin; Zhang, WeiJing

2015-09-01

Cell mechanics plays an important role in cellular physiological activities. Recent studies have shown that cellular mechanical properties are novel biomarkers for indicating the cell states. In this article, temperature-controllable atomic force microscopy (AFM) was applied to quantitatively investigate the effects of temperature and cellular interactions on the mechanics and morphology of human cancer cells. First, AFM indenting experiments were performed on six types of human cells to investigate the changes of cellular Young's modulus at different temperatures and the results showed that the mechanical responses to the changes of temperature were variable for different types of cancer cells. Second, AFM imaging experiments were performed to observe the morphological changes in living cells at different temperatures and the results showed the significant changes of cell morphology caused by the alterations of temperature. Finally, by co-culturing human cancer cells with human immune cells, the mechanical and morphological changes in cancer cells were investigated. The results showed that the co-culture of cancer cells and immune cells could cause the distinct mechanical changes in cancer cells, but no significant morphological differences were observed. The experimental results improved our understanding of the effects of temperature and cellular interactions on the mechanics and morphology of cancer cells.

Small molecular antioxidants effectively protect from PUVA-induced oxidative stress responses underlying fibroblast senescence and photoaging.

PubMed

Briganti, Stefania; Wlaschek, Meinhard; Hinrichs, Christina; Bellei, Barbara; Flori, Enrica; Treiber, Nicolai; Iben, Sebastian; Picardo, Mauro; Scharffetter-Kochanek, Karin

2008-09-01

Exposure of human fibroblasts to 8-methoxypsoralen plus ultraviolet-A irradiation (PUVA) results in stress-induced cellular senescence in fibroblasts. We here studied the role of the antioxidant defense system in the accumulation of reactive oxygen species (ROS) and the effect of the antioxidants alpha-tocopherol, N-acetylcysteine, and alpha-lipoic acid on PUVA-induced cellular senescence. PUVA treatment induced an immediate and increasing generation of intracellular ROS. Supplementation of PUVA-treated fibroblasts with alpha-tocopherol (alpha-Toc), N-acetylcysteine (NAC), or alpha-lipoic acid (alpha-LA) abrogated the increased ROS generation and rescued fibroblasts from the ROS-dependent changes into the cellular senescence phenotype, such as cytoplasmic enlargement, enhanced expression of senescence-associated-beta-galactosidase and matrix-metalloproteinase-1, hallmarks of photoaging and intrinsic aging. PUVA treatment disrupted the integrity of cellular membranes and impaired homeostasis and function of the cellular antioxidant system with a significant decrease in glutathione and hydrogen peroxide-detoxifying enzymes activities. Supplementation with NAC, alpha-LA, and alpha-Toc counteracted these changes. Our data provide causal evidence that (i) oxidative stress due to an imbalance in the overall cellular antioxidant capacity contributes to the induction and maintenance of the PUVA-induced fibroblast senescence and that (ii) low molecular antioxidants protect effectively against these deleterious alterations.

Seasonal variations of cellular stress response of the gilthead sea bream (Sparus aurata).

PubMed

Feidantsis, Konstantinos; Antonopoulou, Efthimia; Lazou, Antigone; Pörtner, Hans O; Michaelidis, Basile

2013-07-01

The present study aimed to investigate the seasonal cellular stress response in vital organs, like the heart, the liver, the whole blood and the skeletal (red and white) muscles of the Mediterranean fish Sparus aurata during a 1-year acclimatization period in the field, in two examined depths (0-2 m and 10-12 m). Processes studied included heat shock protein expression and protein kinase activation. Molecular responses were addressed through the expression of Hsp70 and Hsp90, the phosphorylation of stress-activated protein kinases and particularly p38 mitogen-activated protein kinase (p38 MAPK), the extracellular signal-regulated kinases (ERK-1/2) and c-Jun N-terminal kinases (JNK1/2/3). The induction of Hsp70 and Hsp90 and the phosphorylation of p38 MAPK, JNKs and ERKs in the examined five tissues of the gilthead sea bream indicated a cellular stress response under the prism of a seasonal pattern which was characterized by distinct tissue specificity. Specifically, Hsp induction and MAPK activation occurred before peak summer water temperatures, with no further increases in their levels despite increases in water temperatures. Moreover, although water temperature did not vary significantly with depth of immersion, significant effects of depth on cellular stress response were observed, probably caused by different light regime. The expression and the activation of these certain proteins can be used as tools to define the extreme thermal limits of the gilthead sea bream.

Tissue engineering bioreactor systems for applying physical and electrical stimulations to cells.

PubMed

Jin, GyuHyun; Yang, Gi-Hoon; Kim, GeunHyung

2015-05-01

Bioreactor systems in tissue engineering applications provide various types of stimulation to mimic the tissues in vitro and in vivo. Various bioreactors have been designed to induce high cellular activities, including initial cell attachment, cell growth, and differentiation. Although cell-stimulation processes exert mostly positive effects on cellular responses, in some cases such stimulation can also have a negative effect on cultured cells. In this review, we discuss various types of bioreactor and the positive and negative effects of stimulation (physical, chemical, and electrical) on various cultured cell types. © 2014 Wiley Periodicals, Inc.

Predicting cancer rates in astronauts from animal carcinogenesis studies and cellular markers

NASA Technical Reports Server (NTRS)

Williams, J. R.; Zhang, Y.; Zhou, H.; Osman, M.; Cha, D.; Kavet, R.; Cuccinotta, F.; Dicello, J. F.; Dillehay, L. E.

1999-01-01

The radiation space environment includes particles such as protons and multiple species of heavy ions, with much of the exposure to these radiations occurring at extremely low average dose-rates. Limitations in databases needed to predict cancer hazards in human beings from such radiations are significant and currently do not provide confidence that such predictions are acceptably precise or accurate. In this article, we outline the need for animal carcinogenesis data based on a more sophisticated understanding of the dose-response relationship for induction of cancer and correlative cellular endpoints by representative space radiations. We stress the need for a model that can interrelate human and animal carcinogenesis data with cellular mechanisms. Using a broad model for dose-response patterns which we term the "subalpha-alpha-omega (SAO) model", we explore examples in the literature for radiation-induced cancer and for radiation-induced cellular events to illustrate the need for data that define the dose-response patterns more precisely over specific dose ranges, with special attention to low dose, low dose-rate exposure. We present data for multiple endpoints in cells, which vary in their radiosensitivity, that also support the proposed model. We have measured induction of complex chromosome aberrations in multiple cell types by two space radiations, Fe-ions and protons, and compared these to photons delivered at high dose-rate or low dose-rate. Our data demonstrate that at least three factors modulate the relative efficacy of Fe-ions compared to photons: (i) intrinsic radiosensitivity of irradiated cells; (ii) dose-rate; and (iii) another unspecified effect perhaps related to reparability of DNA lesions. These factors can produce respectively up to at least 7-, 6- and 3-fold variability. These data demonstrate the need to understand better the role of intrinsic radiosensitivity and dose-rate effects in mammalian cell response to ionizing radiation. Such understanding is critical in extrapolating databases between cellular response, animal carcinogenesis and human carcinogenesis, and we suggest that the SAO model is a useful tool for such extrapolation.

Chemical combination effects predict connectivity in biological systems

PubMed Central

Lehár, Joseph; Zimmermann, Grant R; Krueger, Andrew S; Molnar, Raymond A; Ledell, Jebediah T; Heilbut, Adrian M; Short, Glenn F; Giusti, Leanne C; Nolan, Garry P; Magid, Omar A; Lee, Margaret S; Borisy, Alexis A; Stockwell, Brent R; Keith, Curtis T

2007-01-01

Efforts to construct therapeutically useful models of biological systems require large and diverse sets of data on functional connections between their components. Here we show that cellular responses to combinations of chemicals reveal how their biological targets are connected. Simulations of pathways with pairs of inhibitors at varying doses predict distinct response surface shapes that are reproduced in a yeast experiment, with further support from a larger screen using human tumour cells. The response morphology yields detailed connectivity constraints between nearby targets, and synergy profiles across many combinations show relatedness between targets in the whole network. Constraints from chemical combinations complement genetic studies, because they probe different cellular components and can be applied to disease models that are not amenable to mutagenesis. Chemical probes also offer increased flexibility, as they can be continuously dosed, temporally controlled, and readily combined. After extending this initial study to cover a wider range of combination effects and pathway topologies, chemical combinations may be used to refine network models or to identify novel targets. This response surface methodology may even apply to non-biological systems where responses to targeted perturbations can be measured. PMID:17332758

Acute Morphine Administration Reduces Cell-Mediated Immunity and Induces Reactivation of Latent Herpes Simplex Virus Type 1 in BALB/c Mice

PubMed Central

Mojadadi, Shafi; Jamali, Abbas; Khansarinejad, Behzad; Soleimanjahi, Hoorieh; Bamdad, Taravat

2009-01-01

Acute morphine administration is known to alter the course of herpes simplex virus infection. In this study, the effect of acute morphine administration on the reactivation of latent herpes was investigated in a mouse model. Because of the important role of cytolytic T lymphocyte (CTL) activity in the inhibition of herpes simplex virus type 1 (HSV-1) reactivation, the effect of acute morphine administration on CTL responses was also evaluated. Furthermore, lymphocyte proliferation and IFN-γ production were evaluated for their roles in the induction of the CTL response. The findings showed that acute morphine administration significantly reduced CTL responses, lymphocyte proliferation, and IFN-γ production. Furthermore, acute morphine administration has been shown to reactivate latent HSV-1. Previous studies have shown that cellular immune responses have important roles in the inhibition of HSV reactivation. These findings suggest that suppression of a portion of the cellular immune response after acute morphine administration may constitute one part of the mechanism that induces HSV reactivation. PMID:19403060

Effects of Silver and Other Metals on the Cytoskeleton

NASA Technical Reports Server (NTRS)

Conrad, Gary W.

1997-01-01

Directly or indirectly, trace concentrations of silver ion (Ag(+)) stabilize microtubules (Conrad, A.H., et al. Cell Motil. & Cytoskel. 27:117-132), as does taxol (Conrad, A.H., et al. J. Exp. Zool. 262:154-165), an effect with major consequences for cellular shape changes and development. Polymerization of microtubules is gravity-sensitive (Tabony and Job, Proc. Natl. Acad. Sci. USA 89:6948-6952), so trace amounts of Ag(+) may alter cellular ability to respond to gravity. If Ag electrolysis is used to purify water on NASA space vehicles, plants and animals/astronauts will be exposed continuously to Ag(+), a regimen with unknown cellular and developmental consequences. Fertilized eggs of the marine mudsnail, Ilyanassa obsoleta, are the cells in which the effects of A(+) on microtubules were discovered. They distribute visible cytoplasmic contents according to gravity and contain cytoplasmic morphogenetic determinants for heart development. The objectives are to determine if the effects of Ag(+), AU(3+), (of biosensor relevance), or Gd(3+) (inhibitor of some stretch-activated ion channels) on the cytoskeleton (in the presence and absence of mechanical loading) will affect cellular responses to gravity.

Indirect effects of climate changes on cadmium bioavailability and biological effects in the Mediterranean mussel Mytilus galloprovincialis.

PubMed

Nardi, Alessandro; Mincarelli, Luana Fiorella; Benedetti, Maura; Fattorini, Daniele; d'Errico, Giuseppe; Regoli, Francesco

2017-02-01

Despite the great interest in the consequences of climate change on the physiological functioning of marine organisms, indirect and interactive effects of rising temperature and pCO 2 on bioaccumulation and responsiveness to environmental pollutants are still poorly explored, particularly in terms of cellular mechanisms. According to future projections of temperature and pH/pCO 2 , this study investigated the main cellular pathways involved in metal detoxification and oxidative homeostasis in Mediterranean mussels, Mytilus galloprovincialis, exposed for 4 weeks to various combinations of two levels of pH/pCO 2 (8.2/∼400 μatm and 7.4/∼3000 μatm), temperature (20 and 25 °C), and cadmium addition (0 and 20 μg/L). Bioaccumulation was increased in metal exposed organisms but it was not further modulated by different temperature and pH/pCO 2 combinations. However, interactions between temperature, pH and cadmium had significant effects on induction of metallothioneins, responses of the antioxidant system and the onset of oxidative damages, which was tissue dependent. Multiple stressors increased metallothioneins concentrations in the digestive gland revealing different oxidative effects: while temperature and cadmium enhanced glutathione-dependent antioxidant protection and capability to neutralize peroxyl radicals, the metal increased the accumulation of lipid peroxidation products under acidified conditions. Gills did not reveal specific effects for different combinations of factors, but a general stress condition was observed in this tissue after various treatments. Significant variations of immune system were mainly caused by increased temperature and low pH, while co-exposure to acidification and cadmium enhanced metal genotoxicity and the onset of permanent DNA damage in haemocytes. Elaboration of the whole biomarker data in a cellular hazard index, corroborated the synergistic effects of temperature and acidification which increased the toxicological effects of cadmium. The overall results confirmed that climate change could influence ecotoxicological effects of environmental contaminants, highlighting the importance of a better knowledge of cellular mechanisms to understand and predict responsiveness of marine organisms to such multiple stressors. Copyright © 2016 Elsevier Ltd. All rights reserved.

Estrogen and the female heart.

PubMed

Knowlton, A A; Korzick, D H

2014-05-25

Estrogen has a plethora of effects in the cardiovascular system. Studies of estrogen and the heart span human clinical trials and basic cell and molecular investigations. Greater understanding of cell and molecular responses to estrogens can provide further insights into the findings of clinical studies. Differences in expression and cellular/intracellular distribution of the two main receptors, estrogen receptor (ER) α and β, are thought to account for the specificity and differences in responses to estrogen. Much remains to be learned in this area, but cellular distribution within the cardiovascular system is becoming clearer. Identification of GPER as a third ER has introduced further complexity to the system. 17β-estradiol (E2), the most potent human estrogen, clearly has protective properties activating a signaling cascade leading to cellular protection and also influencing expression of the protective heat shock proteins (HSP). E2 protects the heart from ischemic injury in basic studies, but the picture is more involved in the whole organism and clinical studies. Here the complexity of E2's widespread effects comes into play and makes interpretation of findings more challenging. Estrogen loss occurs primarily with aging, but few studies have used aged models despite clear evidence of differences between the response to estrogen deficiency in adult and aged animals. Thus more work is needed focusing on the effects of aging vs. estrogen loss on the cardiovascular system. Published by Elsevier Ireland Ltd.

Cellular track model for study of heavy ion beams

NASA Technical Reports Server (NTRS)

Shinn, Judy L.; Katz, Robert; Cucinotta, Francis A.; Wilson, John W.; Ngo, Duc M.

1993-01-01

Track theory is combined with a realistic model of a heavy ion beam to study the effects of nuclear fragmentation on cell survival and biological effectiveness. The effects of secondary reaction products are studied as a function of depth in a water column. Good agreement is found with experimental results for the survival of human T-l cells exposed to monoenergetic carbon, neon, and argon beams under aerobic and hypoxia conditions. The present calculation, which includes the effect of target fragmentation, is a significant improvement over an earlier calculation because of the use of a vastly improved beam model with no change in the track theory or cellular response parameters.

Autophagy and Cancer

PubMed Central

Mah, Li Yen; Ryan, Kevin M.

2012-01-01

(Macro)autophagy is a cellular membrane trafficking process that serves to deliver cytoplasmic constituents to lysosomes for degradation. At basal levels, it is critical for maintaining cytoplasmic as well as genomic integrity and is therefore key to maintaining cellular homeostasis. Autophagy is also highly adaptable and can be modified to digest specific cargoes to bring about selective effects in response to numerous forms of intracellular and extracellular stress. It is not a surprise, therefore, that autophagy has a fundamental role in cancer and that perturbations in autophagy can contribute to malignant disease. We review here the roles of autophagy in various aspects of tumor suppression including the response of cells to nutrient and hypoxic stress, the control of programmed cell death, and the connection to tumor-associated immune responses. PMID:22166310

Protein aggregation as a cellular response to oxidative stress induced by heme and iron

PubMed Central

Vasconcellos, Luiz R. C.; Dutra, Fabianno F.; Siqueira, Mariana S.; Paula-Neto, Heitor A.; Dahan, Jennifer; Kiarely, Ellen; Carneiro, Leticia A. M.; Bozza, Marcelo T.; Travassos, Leonardo H.

2016-01-01

Hemolytic diseases include a variety of conditions with diverse etiologies in which red blood cells are destroyed and large amounts of hemeproteins are released. Heme has been described as a potent proinflammatory molecule that is able to induce multiple innate immune responses, such as those triggered by TLR4 and the NLRP3 inflammasome, as well as necroptosis in macrophages. The mechanisms by which eukaryotic cells respond to the toxic effects induced by heme to maintain homeostasis are not fully understood, however. Here we describe a previously uncharacterized cellular response induced by heme: the formation of p62/SQTM1 aggregates containing ubiquitinated proteins in structures known as aggresome-like induced structures (ALIS). This action is part of a response driven by the transcription factor NRF2 to the excessive generation of reactive oxygen species induced by heme that results in the expression of genes involved in antioxidant responses, including p62/SQTM1. Furthermore, we show that heme degradation by HO-1 is required for ALIS formation, and that the free iron released on heme degradation is necessary and sufficient to induce ALIS. Moreover, ferritin, a key protein in iron metabolism, prevents excessive ALIS formation. Finally, in vivo, hemolysis promotes an increase in ALIS formation in target tissues. Our data unravel a poorly understood aspect of the cellular responses induced by heme that can be explored to better understand the effects of free heme and free iron during hemolytic diseases such as sickle cell disease, dengue fever, malaria, and sepsis. PMID:27821769

Muscle tissue engineering and regeneration through epigenetic reprogramming and scaffold manipulation

PubMed Central

Tan, S.J.; Fang, J.Y.; Wu, Y.; Yang, Z.; Liang, G.; Han, B.

2015-01-01

Efficiency of cell-based tissue engineering and regenerative medicine has been limited by inadequate cellular responses to injury because of aging and poor controllability of cellular interactions. Since cell progression is under a tight epigenetic regulation, epigenetic modulators such as 5-azacytidine (5-Aza-CR) have been utilized to facilitate reprogramming and development of somatic cells in 2-dimensional (2-D) settings. Nonetheless, progression of a specific tissue lineage toward the terminal phenotype is dependent not only on the genomic potential, but also on the microenvironment cues that are beyond the capability of 2-D approaches. In this study, we investigated the combined effects of matrices of variable rigidities and the treatment with the epigenetic modulator 5-Aza-CR on reprogramming adipose-derived stromal cells (ADSCs) into myoblast-like cells by utilizing tunable transglutaminase cross-linked gelatin (Col-Tgel) in vitro and in vivo. Our experiments demonstrated that cellular plasticity and trans-differentiation were significantly enhanced when ADSCs were treated with an effective dose of 5-Aza-CR (1.25 to 12.5 ng) in the optimal myogenic matrix (15 ± 5 kPa Col-Tgel). Our findings suggest that both physical signals and chemical milieu are critical for the regulation of cellular responses. PMID:26548559

A cell impedance measurement device for the cytotoxicity assay dependent on the velocity of supplied toxic fluid

NASA Astrophysics Data System (ADS)

Kang, Yoon-Tae; Kim, Min-Ji; Cho, Young-Ho

2018-04-01

We present a cell impedance measurement chip capable of characterizing the toxic response of cells depending on the velocity of the supplied toxic fluid. Previous impedance-based devices using a single open-top chamber have been limited to maintaining a constant supply velocity, and devices with a single closed-top chamber present difficulties in simultaneous cytotoxicity assay for varying levels of supply velocities. The present device, capable of generating constant and multiple levels of toxic fluid velocity simultaneously within a single stepwise microchannel, performs a cytotoxicity assay dependent on toxic fluid velocity, in order to find the effective velocity of toxic fluid to cells for maximizing the cytotoxic effect. We analyze the cellular toxic response of 5% ethanol media supplied to cancer cells within a toxic fluid velocity range of 0-8.3 mm s-1. We observe the velocity-dependent cell detachment rate, impedance, and death rate. We find that the cell detachment rate decreased suddenly to 2.4% at a velocity of 4.4 mm s-1, and that the change rates of cell resistance and cell capacitance showed steep decreases to 8% and 41%, respectively, at a velocity of 5.7 mm s-1. The cell death rate and impedance fell steeply to 32% at a velocity of 5.7 mm s-1. We conclude that: (1) the present device is useful in deciding on the toxic fluid velocity effective to cytotoxicity assay, since the cellular toxic response is dependent on the velocity of toxic fluid, and; (2) the cell impedance analysis facilitates a finer cellular response analysis, showing better correlation with the cell death rate, compared to conventional visual observation. The present device, capable of performing the combinational analysis of toxic fluid velocity and cell impedance, has potential for application to the fine cellular toxicity assay of drugs with proper toxic fluid velocity.

Predicting in vivo cardiovascular properties of β-blockers from cellular assays: a quantitative comparison of cellular and cardiovascular pharmacological responses

PubMed Central

Baker, Jillian G.; Kemp, Philip; March, Julie; Fretwell, Laurice; Hill, Stephen J.; Gardiner, Sheila M.

2011-01-01

β-Adrenoceptor antagonists differ in their degree of partial agonism. In vitro assays have provided information on ligand affinity, selectivity, and intrinsic efficacy. However, the extent to which these properties are manifest in vivo is less clear. Conscious freely moving rats, instrumented for measurement of heart rate (β1; HR) and hindquarters vascular conductance (β2; HVC) were used to measure receptor selectivity and ligand efficacy in vivo. CGP 20712A caused a dose-dependent decrease in basal HR (P<0.05, ANOVA) at 5 doses between 6.7 and 670 μg/kg (i.v.) and shifted the dose-response curve for isoprenaline to higher agonist concentrations without altering HVC responses. In contrast, at doses of 67 μg/kg (i.v.) and above, ICI 118551 substantially reduced the HVC response to isoprenaline without affecting HR responses. ZD 7114, xamoterol, and bucindolol significantly increased basal HR (ΔHR: +122±12, +129±11, and +59±11 beats/min, respectively; n=6), whereas other β-blockers caused significant reductions (all at 2 mg/kg i.v.). The agonist effects of xamoterol and ZD 7114 were equivalent to that of the highest dose of isoprenaline. Bucindolol, however, significantly antagonized the response to the highest doses isoprenaline. An excellent correlation was obtained between in vivo and in vitro measures of β1-adrenoceptor efficacy (R2=0.93; P<0.0001).—Baker, J. G., Kemp, P., March, J., Fretwell, L., Hill, S. J., Gardiner, S. M. Predicting in vivo cardiovascular properties of β-blockers from cellular assays: a quantitative comparison of cellular and cardiovascular pharmacological responses. PMID:21865315

Modulatory effects of vitamin D on peripheral cellular immunity in patients with recurrent miscarriage.

PubMed

Chen, Xian; Yin, Biao; Lian, Ruo-Chun; Zhang, Tao; Zhang, Hong-Zhan; Diao, Liang-Hui; Li, Yu-Ye; Huang, Chun-Yu; Liang, De-Sheng; Zeng, Yong

2016-12-01

We aimed to investigate the modulatory effects of vitamin D on peripheral blood cellular immune response in patients with recurrent miscarriage (RM). The effect of vitamin D on the number of peripheral blood cells, T helper 1 (Th1) cytokines, and NK cytotoxicity was measured in 99 women with RM. The percentage of CD19 + B cells and NK cytotoxicity at an effector-to-target cell (E:T) ratio of 50:1, 25:1, and 12.5:1 were significantly higher in the vitamin D insufficiency group (VDI) than in the vitamin D normal group (VDN) (P<.05 each). The proportion of TNF-α-expressing Th cells was significantly higher in the vitamin D deficiency group (VDD) than in VDN (P<.05). However, there were no significant differences between VDI and VDD. This dysregulation was significantly reduced with 1,25(OH) 2 D supplementation. The data suggest that the abnormalities of cellular immune response were observed in RM patients with a low vitamin D level, which could be regulated to some extent with 1,25(OH) 2 D supplementation. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Mechanisms of motor recovery after subtotal spinal cord injury: insights from the study of mice carrying a mutation (WldS) that delays cellular responses to injury.

PubMed

Zhang, Z; Guth, L; Steward, O

1998-01-01

Partial lesions of the mammalian spinal cord result in an immediate motor impairment that recovers gradually over time; however, the cellular mechanisms responsible for the transient nature of this paralysis have not been defined. A unique opportunity to identify those injury-induced cellular responses that mediate the recovery of function has arisen from the discovery of a unique mutant strain of mice in which the onset of Wallerian degeneration is dramatically delayed. In this strain of mice (designated WldS for Wallerian degeneration, slow), many of the cellular responses to spinal cord injury are also delayed. We have used this experimental animal model to evaluate possible causal relationships between these delayed cellular responses and the onset of functional recovery. For this purpose, we have compared the time course of locomotor recovery in C57BL/6 (control) mice and in WldS (mutant) mice by hemisecting the spinal cord at T8 and evaluating locomotor function at daily postoperative intervals. The time course of locomotor recovery (as determined by the Tarlov open-field walking procedure) was substantially delayed in mice carrying the WldS mutation: C57BL/6 control mice began to stand and walk within 6 days (mean Tarlov score of 4), whereas mutant mice did not exhibit comparable locomotor function until 16 days postoperatively. (a) The rapid return of locomotor function in the C57BL/6 mice suggests that the recovery resulted from processes of functional plasticity rather than from regeneration or collateral sprouting of nerve fibers. (b) The marked delay in the return of locomotor function in WldS mice indicates that the processes of neuroplasticity are induced by degenerative changes in the damaged neurons. (c) These strains of mice can be effectively used in future studies to elucidate the specific biochemical and physiological alterations responsible for inducing functional plasticity and restoring locomotor function after spinal cord injury.

Pyridostigmine bromide (PYR) alters immune function in B6C3F1 mice.

PubMed

Peden-Adams, M M; Dudley, A C; EuDaly, J G; Allen, C T; Gilkeson, G S; Keil, D E

2004-02-01

Pyridostigmine bromide (PYR) is an anticholinesterase drug indicated for the treatment of myasthenia gravis and neuromuscular blockade reversal. It acts as a reversible cholinesterase inhibitor and was used as a pretreatment for soldiers during Operation Desert Storm to protect against possible nerve gas attacks. Since that time, PYR has been implicated as a possible causative agent contributing to Gulf War Illness. PYR's mechanism of action has been well-delineated with regards to its effects on the nervous system, yet little is known regarding potential effects on immunological function. To evaluate the effects of PYR on immunological function, adult female B6C3F1 mice were gavaged daily for 14 days with PYR (0, 1, 5, 10, or 20 mg/kg/day). Immune parameters assessed were lymphoproliferation, natural killer cell activity, the SRBC-specific antibody plaque-forming cell (PFC) response, thymus and spleen weight and cellularity, and thymic and splenic CD4/CD8 lymphocyte subpopulations. Exposure to PYR did not alter splenic and thymus weight or splenic cellularity. However, 20 mg PYR/kg/day decreased thymic cellularity with decreases in both CD4+/CD8+ (20 mg/kg/day) and CD4-/CD8- (10 and 20 mg/kg/day) cell types. Functional immune assays indicated that lymphocyte proliferative responses and natural killer cell activity were normal; whereas exposure to PYR significantly decreased primary IgM antibody responses to a T-cell dependent antigen at the 1, 5, 10 and 20 mg/kg treatment levels for 14 days. This is the first study to examine the immunotoxicological effects of PYR and demonstrate that this compound selectively suppresses humoral antibody responses.

Effects of Radiation on Rat Retina after 18 days of Space Flight

NASA Technical Reports Server (NTRS)

Philpott, D.; Corbett, R.; Turnbill, C.; Black, S.; Dayhoff, D.; McGourty, J.; Lee, R.; Harrison, G.; Savick, L.

1978-01-01

Although cumulative effects an retina from low-dose radiation during prolonged spaceflight are not known, ary impairment of vision could set limits for spaceflight duration. Cosmic rays are now considered to be the cause of the "light flashes" seen during spaceflight by activating retina cells as they pass through the photoreceptors. Previous studies have also shown retinal cellular alterations and cell necrosis from high-energy, particle (HZE) radiation. Ten rats, 5 centrifuged during flight (FC) to simulate gravity and 5 in-flight stationary (FS) experiencing hypogravity, orbited Earth for 18.5 days on Cosmos 936. The animals were sacrificed 25 days post-recovery and the eyes flown to Ames Res. Ctr. The pattern of cell necrosis in the retinas from the FC group showed the same response to radiation as the FS. This would indicate that hypogravity was not a factor in the observed results. Also the cellular response in the retinas exposed in the Berkeley accelerator again matched both the FC and FS eyes. Thus all three conditions provide comparable changes and indicate HZE particles as the possible cause of the cellular alterations, channels, and breakdown.

Predicting Glucose Sensor Behavior in Blood Using Transport Modeling: Relative Impacts of Protein Biofouling and Cellular Metabolic Effects

PubMed Central

Novak, Matthew T.; Yuan, Fan; Reichert, William M.

2013-01-01

Background Tissue response to indwelling glucose sensors remains a confounding barrier to clinical application. While the effects of fully formed capsular tissue on sensor response have been studied, little has been done to understand how tissue interactions occurring before capsule formation hinder sensor performance. Upon insertion in subcutaneous tissue, the sensor is initially exposed to blood, blood borne constituents, and interstitial fluid. Using human whole blood as a simple ex vivo experimental system, the effects of protein accumulation at the sensor surface (biofouling effects) and cellular consumption of glucose in both the biofouling layer and in the bulk (metabolic effects) on sensor response were assessed. Methods Medtronic MiniMed SofSensor glucose sensors were incubated in whole blood, plasma-diluted whole blood, and cell-free platelet-poor plasma (PPP) to analyze the impact of different blood constituents on sensor function. Experimental conditions were then simulated using MATLAB to predict the relative impacts of biofouling and metabolic effects on the observed sensor responses. Results Protein biofouling in PPP in both the experiments and the simulations was found to have no interfering effect upon sensor response. Experimental results obtained with whole and dilute blood showed that the sensor response was markedly affected by blood borne glucose-consuming cells accumulated in the biofouling layer and in the surrounding bulk. Conclusions The physical barrier to glucose transport presented by protein biofouling does not hinder glucose movement to the sensor surface, and the consumption of glucose by inflammatory cells, and not erythrocytes, proximal to the sensor surface has a substantial effect on sensor response and may be the main culprit for anomalous sensor behavior immediately following implantation. PMID:24351181

Protective Cellular Immunity Against Influenza Virus Induced by Plasmid Inoculation of Newborn Mice

PubMed Central

Bot, Adrian; Bot, Simona; García-Sastre, Adolfo

1998-01-01

Neonate organisms display an intrinsic disability to mount effective immune responses to infectious agents or conventional vaccines. Whereas low. doses of antigens trigger a suboptimal response, higher doses are frequently associated with tolerance induction. We investigated the ability of a plasmid-expressing nucleoprotein of influenza virus to prime a specific cellular immune response when administered to newborn mice. We found that persistent exposure to antigen following plasmid inoculation of neonates leads to a vigorous priming of specific CTLs rather than tolerance induction. The CTLs were cross-reactive against multiple strains of type A influenza viruses and produced IFNγ but no IL-4. The immunity triggered by plasmid inoculation of neonates was protective in terms of pulmonary virus clearance as well as survival rate following lethal challenge with influenza virus. Whereas the persistence of the plasmid at the site of injection was readily demonstrable in adult mice at 3 months after inoculation, mice immunized as newborns displayed no plasmid at 3 months and very little at 1 month after injection. Thus, DNA-based immunization of neonates may prove an effective and safe vaccination strategy for induction of cellular immunity against microbes that cause serious infectious diseases in the early period of life. PMID:9851359

Cell death induced by ozone and various non-thermal plasmas: therapeutic perspectives and limitations

PubMed Central

Lunov, Oleg; Zablotskii, Vitalii; Churpita, Olexander; Chánová, Eliška; Syková, Eva; Dejneka, Alexandr; Kubinová, Šárka

2014-01-01

Non-thermal plasma has been recognized as a promising tool across a vast variety of biomedical applications, with the potential to create novel therapeutic methods. However, the understanding of the molecular mechanisms behind non-thermal plasma cellular effects remains a significant challenge. In this study, we show how two types of different non-thermal plasmas induce cell death in mammalian cell cultures via the formation of multiple intracellular reactive oxygen/nitrogen species. Our results showed a discrepancy in the superoxide accumulation and lysosomal activity in response to air and helium plasma, suggesting that triggered signalling cascades might be grossly different between different plasmas. In addition, the effects of ozone, a considerable component of non-thermal plasma, have been simultaneously evaluated and have revealed much faster and higher cytotoxic effects. Our findings offer novel insight into plasma-induced cellular responses, and provide a basis for better controlled biomedical applications. PMID:25410636

The role of actin networks in cellular mechanosensing

NASA Astrophysics Data System (ADS)

Azatov, Mikheil

Physical processes play an important role in many biological phenomena, such as wound healing, organ development, and tumor metastasis. During these processes, cells constantly interact with and adapt to their environment by exerting forces to mechanically probe the features of their surroundings and generating appropriate biochemical responses. The mechanisms underlying how cells sense the physical properties of their environment are not well understood. In this thesis, I present my studies to investigate cellular responses to the stiffness and topography of the environment. In order to sense the physical properties of their environment, cells dynamically reorganize the structure of their actin cytoskeleton, a dynamic network of biopolymers, altering the shape and spatial distribution of protein assemblies. Several observations suggest that proteins that crosslink actin filaments may play an important role in cellular mechanosensitivity. Palladin is an actin-crosslinking protein that is found in the lamellar actin network, stress fibers and focal adhesions, cellular structures that are critical for mechanosensing of the physical environment. By virtue of its close interactions with these structures in the cell, palladin may play an important role in cell mechanics. However, the role of actin crosslinkers in general, and palladin in particular, in cellular force generation and mechanosensing is not well known. I have investigated the role of palladin in regulating the plasticity of the actin cytoskeleton and cellular force generation in response to alterations in substrate stiffness. I have shown that the expression levels of palladin modulate the forces exerted by cells and their ability to sense substrate stiffness. Perturbation experiments also suggest that palladin levels in cells altered myosin motor activity. These results suggest that the actin crosslinkers, such as palladin, and myosin motors coordinate for optimal cell function and to prevent aberrant behavior as in cancer metastasis. In addition to stiffness, the local geometry or topography of the surface has been shown to modulate the movement, morphology, and cytoskeletal organization of cells. However, the effect of topography on fluctuations of intracellular structures, which arise from motor driven activity on a viscoelastic actin network are not known. I have used nanofabricated substrates with parallel ridges to show that the cell shape, the actin cytoskeleton and focal adhesions all align along the direction of the ridges, exhibiting a biphasic dependence on the spacing between ridges. I further demonstrated that palladin bands along actin stress fibers undergo a complex diffusive motion with velocities aligned along the direction of ridges. These results provide insight into the mechanisms of cellular mechanosensing of the environment, suggesting a complex interplay between the actin cytoskeleton and cellular adhesions in coordinating cellular response to surface topography. Overall, this work has advanced our understanding of mechanisms that govern cellular responses to their physical environment.

Cellular Response to Bleomycin-Induced DNA Damage in Human Fibroblast Cells in Space

NASA Technical Reports Server (NTRS)

Lu, Tao; Zhang, Ye; Wong, Michael; Stodieck, Louis; Karouia, Fathi; Wu, Honglu

2015-01-01

Outside the protection of the geomagnetic field, astronauts and other living organisms are constantly exposed to space radiation that consists of energetic protons and other heavier charged particles. Whether spaceflight factors, microgravity in particular, have effects on cellular responses to DNA damage induced by exposure to radiation or cytotoxic chemicals is still unknown, as is their impact on the radiation risks for astronauts and on the mutation rate in microorganisms. Although possible synergistic effects of space radiation and other spaceflight factors have been investigated since the early days of the human space program, the published results were mostly conflicting and inconsistent. To investigate effects of spaceflight on cellular responses to DNA damages, human fibroblast cells flown to the International Space Station (ISS) were treated with bleomycin for three hours in the true microgravity environment, which induced DNA damages including double-strand breaks (DSB) similar to the ionizing radiation. Damages in the DNA were measured by the phosphorylation of a histone protein H2AX (g-H2AX), which showed slightly more foci in the cells on ISS than in the ground control. The expression of genes involved in DNA damage response was also analyzed using the PCR array. Although a number of the genes, including CDKN1A and PCNA, were significantly altered in the cells after bleomycin treatment, no significant difference in the expression profile of DNA damage response genes was found between the flight and ground samples. At the time of the bleomycin treatment, the cells on the ISS were found to be proliferating faster than the ground control as measured by the percentage of cells containing positive Ki-67 signals. Our results suggested that the difference in g-H2AX focus counts between flight and ground was due to the faster growth rate of the cells in space, but spaceflight did not affect initial transcriptional responses of the DNA damage response genes to bleomycin treatment.

Systems Biology for Organotypic Cell Cultures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grego, Sonia; Dougherty, Edward R.; Alexander, Francis J.

Translating in vitro biological data into actionable information related to human health holds the potential to improve disease treatment and risk assessment of chemical exposures. While genomics has identified regulatory pathways at the cellular level, translation to the organism level requires a multiscale approach accounting for intra-cellular regulation, inter-cellular interaction, and tissue/organ-level effects. Tissue-level effects can now be probed in vitro thanks to recently developed systems of three-dimensional (3D), multicellular, “organotypic” cell cultures, which mimic functional responses of living tissue. However, there remains a knowledge gap regarding interactions across different biological scales, complicating accurate prediction of health outcomes from molecular/genomicmore » data and tissue responses. Systems biology aims at mathematical modeling of complex, non-linear biological systems. We propose to apply a systems biology approach to achieve a computational representation of tissue-level physiological responses by integrating empirical data derived from organotypic culture systems with computational models of intracellular pathways to better predict human responses. Successful implementation of this integrated approach will provide a powerful tool for faster, more accurate and cost-effective screening of potential toxicants and therapeutics. On September 11, 2015, an interdisciplinary group of scientists, engineers, and clinicians gathered for a workshop in Research Triangle Park, North Carolina, to discuss this ambitious goal. Participants represented laboratory-based and computational modeling approaches to pharmacology and toxicology, as well as the pharmaceutical industry, government, non-profits, and academia. Discussions focused on identifying critical system perturbations to model, the computational tools required, and the experimental approaches best suited to generating key data. This consensus report summarizes the discussions held.« less

Workshop Report: Systems Biology for Organotypic Cell Cultures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grego, Sonia; Dougherty, Edward R.; Alexander, Francis Joseph

Translating in vitro biological data into actionable information related to human health holds the potential to improve disease treatment and risk assessment of chemical exposures. While genomics has identified regulatory pathways at the cellular level, translation to the organism level requires a multiscale approach accounting for intra-cellular regulation, inter-cellular interaction, and tissue/organ-level effects. Tissue-level effects can now be probed in vitro thanks to recently developed systems of three-dimensional (3D), multicellular, “organotypic” cell cultures, which mimic functional responses of living tissue. However, there remains a knowledge gap regarding interactions across different biological scales, complicating accurate prediction of health outcomes from molecular/genomicmore » data and tissue responses. Systems biology aims at mathematical modeling of complex, non-linear biological systems. We propose to apply a systems biology approach to achieve a computational representation of tissue-level physiological responses by integrating empirical data derived from organotypic culture systems with computational models of intracellular pathways to better predict human responses. Successful implementation of this integrated approach will provide a powerful tool for faster, more accurate and cost-effective screening of potential toxicants and therapeutics. On September 11, 2015, an interdisciplinary group of scientists, engineers, and clinicians gathered for a workshop in Research Triangle Park, North Carolina, to discuss this ambitious goal. Participants represented laboratory-based and computational modeling approaches to pharmacology and toxicology, as well as the pharmaceutical industry, government, non-profits, and academia. Discussions focused on identifying critical system perturbations to model, the computational tools required, and the experimental approaches best suited to generating key data.« less

Workshop Report: Systems Biology for Organotypic Cell Cultures

DOE PAGES

Grego, Sonia; Dougherty, Edward R.; Alexander, Francis Joseph; ...

2016-11-14

Translating in vitro biological data into actionable information related to human health holds the potential to improve disease treatment and risk assessment of chemical exposures. While genomics has identified regulatory pathways at the cellular level, translation to the organism level requires a multiscale approach accounting for intra-cellular regulation, inter-cellular interaction, and tissue/organ-level effects. Tissue-level effects can now be probed in vitro thanks to recently developed systems of three-dimensional (3D), multicellular, “organotypic” cell cultures, which mimic functional responses of living tissue. However, there remains a knowledge gap regarding interactions across different biological scales, complicating accurate prediction of health outcomes from molecular/genomicmore » data and tissue responses. Systems biology aims at mathematical modeling of complex, non-linear biological systems. We propose to apply a systems biology approach to achieve a computational representation of tissue-level physiological responses by integrating empirical data derived from organotypic culture systems with computational models of intracellular pathways to better predict human responses. Successful implementation of this integrated approach will provide a powerful tool for faster, more accurate and cost-effective screening of potential toxicants and therapeutics. On September 11, 2015, an interdisciplinary group of scientists, engineers, and clinicians gathered for a workshop in Research Triangle Park, North Carolina, to discuss this ambitious goal. Participants represented laboratory-based and computational modeling approaches to pharmacology and toxicology, as well as the pharmaceutical industry, government, non-profits, and academia. Discussions focused on identifying critical system perturbations to model, the computational tools required, and the experimental approaches best suited to generating key data.« less

Systems biology for organotypic cell cultures.

PubMed

Grego, Sonia; Dougherty, Edward R; Alexander, Francis J; Auerbach, Scott S; Berridge, Brian R; Bittner, Michael L; Casey, Warren; Cooley, Philip C; Dash, Ajit; Ferguson, Stephen S; Fennell, Timothy R; Hawkins, Brian T; Hickey, Anthony J; Kleensang, Andre; Liebman, Michael N J; Martin, Florian; Maull, Elizabeth A; Paragas, Jason; Qiao, Guilin Gary; Ramaiahgari, Sreenivasa; Sumner, Susan J; Yoon, Miyoung

2017-01-01

Translating in vitro biological data into actionable information related to human health holds the potential to improve disease treatment and risk assessment of chemical exposures. While genomics has identified regulatory pathways at the cellular level, translation to the organism level requires a multiscale approach accounting for intra-cellular regulation, inter-cellular interaction, and tissue/organ-level effects. Tissue-level effects can now be probed in vitro thanks to recently developed systems of three-dimensional (3D), multicellular, "organotypic" cell cultures, which mimic functional responses of living tissue. However, there remains a knowledge gap regarding interactions across different biological scales, complicating accurate prediction of health outcomes from molecular/genomic data and tissue responses. Systems biology aims at mathematical modeling of complex, non-linear biological systems. We propose to apply a systems biology approach to achieve a computational representation of tissue-level physiological responses by integrating empirical data derived from organotypic culture systems with computational models of intracellular pathways to better predict human responses. Successful implementation of this integrated approach will provide a powerful tool for faster, more accurate and cost-effective screening of potential toxicants and therapeutics. On September 11, 2015, an interdisciplinary group of scientists, engineers, and clinicians gathered for a workshop in Research Triangle Park, North Carolina, to discuss this ambitious goal. Participants represented laboratory-based and computational modeling approaches to pharmacology and toxicology, as well as the pharmaceutical industry, government, non-profits, and academia. Discussions focused on identifying critical system perturbations to model, the computational tools required, and the experimental approaches best suited to generating key data.

Mechanisms of Optical Regression Following Corneal Laser Refractive Surgery: Epithelial and Stromal Responses

PubMed Central

MOSHIRFAR, Majid; DESAUTELS, Jordan D.; WALKER, Brian D.; MURRI, Michael S.; BIRDSONG, Orry C.; HOOPES, Phillip C. Sr

2018-01-01

Laser vision correction is a safe and effective method of reducing spectacle dependence. Photorefractive Keratectomy (PRK), Laser In Situ Keratomileusis (LASIK), and Small-Incision Lenticule Extraction (SMILE) can accurately correct myopia, hyperopia, and astigmatism. Although these procedures are nearing optimization in terms of their ability to produce a desired refractive target, the long term cellular responses of the cornea to these procedures can cause patients to regress from the their ideal postoperative refraction. In many cases, refractive regression requires follow up enhancement surgeries, presenting additional risks to patients. Although some risk factors underlying refractive regression have been identified, the exact mechanisms have not been elucidated. It is clear that cellular proliferation events are important mediators of optical regression. This review focused specifically on cellular changes to the corneal epithelium and stroma, which may influence postoperative visual regression following LASIK, PRK, and SMILE procedures. PMID:29644238

Gradient Material Strategies for Hydrogel Optimization in Tissue Engineering Applications

PubMed Central

2018-01-01

Although a number of combinatorial/high-throughput approaches have been developed for biomaterial hydrogel optimization, a gradient sample approach is particularly well suited to identify hydrogel property thresholds that alter cellular behavior in response to interacting with the hydrogel due to reduced variation in material preparation and the ability to screen biological response over a range instead of discrete samples each containing only one condition. This review highlights recent work on cell–hydrogel interactions using a gradient material sample approach. Fabrication strategies for composition, material and mechanical property, and bioactive signaling gradient hydrogels that can be used to examine cell–hydrogel interactions will be discussed. The effects of gradients in hydrogel samples on cellular adhesion, migration, proliferation, and differentiation will then be examined, providing an assessment of the current state of the field and the potential of wider use of the gradient sample approach to accelerate our understanding of matrices on cellular behavior. PMID:29485612

Functional Implications of Novel Human Acid Sphingomyelinase Splice Variants

PubMed Central

Rhein, Cosima; Tripal, Philipp; Seebahn, Angela; Konrad, Alice; Kramer, Marcel; Nagel, Christine; Kemper, Jonas; Bode, Jens; Mühle, Christiane; Gulbins, Erich; Reichel, Martin; Becker, Cord-Michael; Kornhuber, Johannes

2012-01-01

Background Acid sphingomyelinase (ASM) hydrolyses sphingomyelin and generates the lipid messenger ceramide, which mediates a variety of stress-related cellular processes. The pathological effects of dysregulated ASM activity are evident in several human diseases and indicate an important functional role for ASM regulation. We investigated alternative splicing as a possible mechanism for regulating cellular ASM activity. Methodology/Principal Findings We identified three novel ASM splice variants in human cells, termed ASM-5, -6 and -7, which lack portions of the catalytic- and/or carboxy-terminal domains in comparison to full-length ASM-1. Differential expression patterns in primary blood cells indicated that ASM splicing might be subject to regulatory processes. The newly identified ASM splice variants were catalytically inactive in biochemical in vitro assays, but they decreased the relative cellular ceramide content in overexpression studies and exerted a dominant-negative effect on ASM activity in physiological cell models. Conclusions/Significance These findings indicate that alternative splicing of ASM is of functional significance for the cellular stress response, possibly representing a mechanism for maintaining constant levels of cellular ASM enzyme activity. PMID:22558155

Differential Fc-receptor engagement drives an anti-tumor vaccinal effect

PubMed Central

DiLillo, David J.; Ravetch, Jeffrey V.

2015-01-01

Summary Passively-administered anti-tumor mAbs rapidly kill tumor targets via FcγR-mediated cytotoxicity (ADCC), a short-term process. However, anti-tumor mAb treatment can also induce a vaccinal effect, in which mAb-mediated tumor death induces a long-term anti-tumor cellular immune response. To determine how such responses are generated, we utilized a murine model of an anti-tumor vaccinal effect against a model neoantigen. We demonstrate that FcγR expression by CD11c+ antigen-presenting cells is required to generate anti-tumor T cell responses upon ADCC-mediated tumor clearance. Using FcγR-humanized mice, we demonstrate that anti-tumor huIgG1 must engage hFcγRIIIA on macrophages to mediate ADCC, but also engage hFcγRIIA, the sole hFcγR expressed by human DCs, to generate a potent vaccinal effect. Thus, while next-generation anti-tumor antibodies with enhanced binding to only hFcγRIIIA are now in clinical use, ideal anti-tumor antibodies must be optimized for both cytotoxic effects as well as hFcγRIIA engagement on DCs to stimulate long-term anti-tumor cellular immunity. PMID:25976835

Evaluation of the effects of active fractions of chinese medicine formulas on IL-1β, IL-6, and TNF-α release from ANA-1 murine macrophages.

PubMed

Ni, Li-Jun; Wang, Nan-Nan; Zhang, Li-Guo; Guo, Yan-Zi; Shi, Wan-Zhong

2016-02-17

Yaotongning (YTN) is a traditional Chinese Medicine (TCM) that contains ten component medicinal materials (CMMs) and uses Chinese rice wine as a vehicle to enhance its efficacy. YTN has been used for rheumatoid arthritis (RA) treatment in China for decades and has been reported to have anti-inflammatory and analgesic effects, as well as to strengthen the immune system. The present work quantitatively evaluated the in vitro effects of active fractions from the ten CMMs that make up YTN and eight additional herbs commonly used in TCM formulas for RA treatment, as well as different combinations of these active fractions, on cellular immune response; the findings were used to determine which active fractions are responsible for promoting an immune response, and to assess whether YTN is superior to other similar formulas and whether YTN can be improved by simplifying its formula from the point of its cellular immunomodulatory activity. Using the YTN formulation principles and some concepts in combinatorial chemistry, 27 TCM samples were designed by combining some or all of the active fractions of YTN and other eight herbs used for RA treatment. Release of interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) from ANA-1 murine macrophages was measured using an enzyme-linked immunosorbent assay (ELISA). The immunoregulatory effects of the TCM samples were evaluated by comparing their half-effective concentrations (EC50) for stimulating the release of these cytokines. Among the investigated active fractions, the flavonoids from Carthamus tinctorius (Fct), Davallia mariesii (Fdm), and Cinnamomum cassia Twig volatile oils (Vca) from the eight selected herbs effectively promoted IL-1β and IL-6 release from ANA-1 cells. Saponins from the YTN CMM Glycyrrhiza uralensis (Sgu) were the most potent promoters of IL-1β and TNF-α release. The aqueous extract of YTN CMM Eupolyphaga sinensis (Ves) strongly enhanced the release of IL-1β, IL-6, and TNF-α from ANA-1 cells. The EC50 values for stimulating the secretion of IL-1β, IL-6, and TNF-α could be determined for only six samples. The full YTN formula and the sample containing 50% Glycyrrhiza uralensis saponins, 25% of the mixture of alkaloids, and 25% of the mixture of all flavonoids exhibited good comprehensive cellular immunomodulatory activity. The immunomodulatory activity of the complete YTN formula was better than that of the sample containing all active fractions of YTN without Chinese rice wine (the YTN vehicle). Sgu and Ves are the primary active fractions of YTN involved in stimulating immune responses. The YTN prescription was reasonably effective at promoting cellular immune responses. Chinese rice wine, the YTN vehicle, strengthened the immunoregulatory activity of YTN. The results of this study demonstrate that the YTN recipe could be improved by reducing the number of CMMs and altering some active fractions without reducing its activity to promote cellular immune responses. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Calcium impacts carbon and nitrogen balance in the filamentous cyanobacterium Anabaena sp. PCC 7120

PubMed Central

Walter, Julia; Lynch, Fiona; Battchikova, Natalia; Aro, Eva-Mari

2016-01-01

Calcium is integral to the perception, communication and adjustment of cellular responses to environmental changes. However, the role of Ca2+ in fine-tuning cellular responses of wild-type cyanobacteria under favourable growth conditions has not been examined. In this study, extracellular Ca2+ has been altered, and changes in the whole transcriptome of Anabaena sp. PCC 7120 have been evaluated under conditions replete of carbon and combined nitrogen. Ca2+ induced differential expression of many genes driving primary cellular metabolism, with transcriptional regulation of carbon- and nitrogen-related processes responding with opposing trends. However, physiological effects of these transcriptional responses on biomass accumulation, biomass composition, and photosynthetic activity over the 24h period following Ca2+ adjustment were found to be minor. It is well known that intracellular carbon:nitrogen balance is integral to optimal cell growth and that Ca2+ plays an important role in the response of heterocystous cyanobacteria to combined-nitrogen deprivation. This work adds to the current knowledge by demonstrating a signalling role of Ca2+ for making sensitive transcriptional adjustments required for optimal growth under non-limiting conditions. PMID:27012282

Calcium impacts carbon and nitrogen balance in the filamentous cyanobacterium Anabaena sp. PCC 7120.

PubMed

Walter, Julia; Lynch, Fiona; Battchikova, Natalia; Aro, Eva-Mari; Gollan, Peter J

2016-06-01

Calcium is integral to the perception, communication and adjustment of cellular responses to environmental changes. However, the role of Ca(2+) in fine-tuning cellular responses of wild-type cyanobacteria under favourable growth conditions has not been examined. In this study, extracellular Ca(2+) has been altered, and changes in the whole transcriptome of Anabaena sp. PCC 7120 have been evaluated under conditions replete of carbon and combined nitrogen. Ca(2+) induced differential expression of many genes driving primary cellular metabolism, with transcriptional regulation of carbon- and nitrogen-related processes responding with opposing trends. However, physiological effects of these transcriptional responses on biomass accumulation, biomass composition, and photosynthetic activity over the 24h period following Ca(2+) adjustment were found to be minor. It is well known that intracellular carbon:nitrogen balance is integral to optimal cell growth and that Ca(2+) plays an important role in the response of heterocystous cyanobacteria to combined-nitrogen deprivation. This work adds to the current knowledge by demonstrating a signalling role of Ca(2+) for making sensitive transcriptional adjustments required for optimal growth under non-limiting conditions. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Biophoton detection and low-intensity light therapy: a potential clinical partnership.

PubMed

Tafur, Joseph; Van Wijk, Eduard P A; Van Wijk, Roeland; Mills, Paul J

2010-02-01

Low-intensity light therapy (LILT) is showing promise in the treatment of a wide variety of medical conditions. Concurrently, our knowledge of LILT mechanisms continues to expand. We are now aware of LILT's potential to induce cellular effects through, for example, accelerated ATP production and the mitigation of oxidative stress. In clinical use, however, it is often difficult to predict patient response to LILT. It appears that cellular reduction/oxidation (redox) state may play a central role in determining sensitivity to LILT and may help explain variability in patient responsiveness. In LILT, conditions associated with elevated reactive oxygen species (ROS) production, e.g. diabetic hyperglycemia, demonstrate increased sensitivity to LILT. Consequently, assessment of tissue redox conditions in vivo may prove helpful in identifying responsive tissues. A noninvasive redox measure may be useful in advancing investigation in LILT and may one day be helpful in better identifying responsive patients. The detection of biophotons, the production of which is associated with cellular redox state and the generation of ROS, represents just such an opportunity. In this review, we will present the case for pursuing further investigation into the potential clinical partnership between biophoton detection and LILT.

Biophoton Detection and Low-Intensity Light Therapy: A Potential Clinical Partnership

PubMed Central

Van Wijk, Eduard P.A.; Van Wijk, Roeland; Mills, Paul J.

2010-01-01

Abstract Low-intensity light therapy (LILT) is showing promise in the treatment of a wide variety of medical conditions. Concurrently, our knowledge of LILT mechanisms continues to expand. We are now aware of LILT's potential to induce cellular effects through, for example, accelerated ATP production and the mitigation of oxidative stress. In clinical use, however, it is often difficult to predict patient response to LILT. It appears that cellular reduction/oxidation (redox) state may play a central role in determining sensitivity to LILT and may help explain variability in patient responsiveness. In LILT, conditions associated with elevated reactive oxygen species (ROS) production, e.g. diabetic hyperglycemia, demonstrate increased sensitivity to LILT. Consequently, assessment of tissue redox conditions in vivo may prove helpful in identifying responsive tissues. A noninvasive redox measure may be useful in advancing investigation in LILT and may one day be helpful in better identifying responsive patients. The detection of biophotons, the production of which is associated with cellular redox state and the generation of ROS, represents just such an opportunity. In this review, we will present the case for pursuing further investigation into the potential clinical partnership between biophoton detection and LILT. PMID:19754267

Chemotherapeutic response to cisplatin-like drugs in human breast cancer cells probed by vibrational microspectroscopy.

PubMed

Batista de Carvalho, A L M; Pilling, M; Gardner, P; Doherty, J; Cinque, G; Wehbe, K; Kelley, C; Batista de Carvalho, L A E; Marques, M P M

2016-06-23

Studies of drug-cell interactions in cancer model systems are essential in the preclinical stage of rational drug design, which relies on a thorough understanding of the mechanisms underlying cytotoxic activity and biological effects, at a molecular level. This study aimed at applying complementary vibrational spectroscopy methods to evaluate the cellular impact of two Pt(ii) and Pd(ii) dinuclear chelates with spermine (Pt2Spm and Pd2Spm), using cisplatin (cis-Pt(NH3)2Cl2) as a reference compound. Their effects on cellular metabolism were monitored in a human triple-negative metastatic breast cancer cell line (MDA-MB-231) by Raman and synchrotron-radiation infrared microspectroscopies, for different drug concentrations (2-8 μM) at 48 h exposure. Multivariate data analysis was applied (unsupervised PCA), unveiling drug- and concentration-dependent effects: apart from discrimination between control and drug-treated cells, a clear separation was obtained for the different agents studied - mononuclear vs. polynuclear, and Pt(ii) vs. Pd(ii). Spectral biomarkers of drug action were identified, as well as the cellular response to the chemotherapeutic insult. The main effect of the tested compounds was found to be on DNA, lipids and proteins, the Pd(ii) agent having a more significant impact on proteins while its Pt(ii) homologue affected the cellular lipid content at lower concentrations, which suggests the occurrence of distinct and unconventional pathways of cytotoxicity for these dinuclear polyamine complexes. Raman and FTIR microspectroscopies were confirmed as powerful non-invasive techniques to obtain unique spectral signatures of the biochemical impact and physiological reaction of cells to anticancer agents.

Network representations of immune system complexity

PubMed Central

Subramanian, Naeha; Torabi-Parizi, Parizad; Gottschalk, Rachel A.; Germain, Ronald N.; Dutta, Bhaskar

2015-01-01

The mammalian immune system is a dynamic multi-scale system composed of a hierarchically organized set of molecular, cellular and organismal networks that act in concert to promote effective host defense. These networks range from those involving gene regulatory and protein-protein interactions underlying intracellular signaling pathways and single cell responses to increasingly complex networks of in vivo cellular interaction, positioning and migration that determine the overall immune response of an organism. Immunity is thus not the product of simple signaling events but rather non-linear behaviors arising from dynamic, feedback-regulated interactions among many components. One of the major goals of systems immunology is to quantitatively measure these complex multi-scale spatial and temporal interactions, permitting development of computational models that can be used to predict responses to perturbation. Recent technological advances permit collection of comprehensive datasets at multiple molecular and cellular levels while advances in network biology support representation of the relationships of components at each level as physical or functional interaction networks. The latter facilitate effective visualization of patterns and recognition of emergent properties arising from the many interactions of genes, molecules, and cells of the immune system. We illustrate the power of integrating ‘omics’ and network modeling approaches for unbiased reconstruction of signaling and transcriptional networks with a focus on applications involving the innate immune system. We further discuss future possibilities for reconstruction of increasingly complex cellular and organism-level networks and development of sophisticated computational tools for prediction of emergent immune behavior arising from the concerted action of these networks. PMID:25625853

Plant-Derived Polyphenols in Human Health: Biological Activity, Metabolites and Putative Molecular Targets.

PubMed

Olivares-Vicente, Marilo; Barrajon-Catalan, Enrique; Herranz-Lopez, Maria; Segura-Carretero, Antonio; Joven, Jorge; Encinar, Jose Antonio; Micol, Vicente

2018-01-01

Hibiscus sabdariffa, Lippia citriodora, Rosmarinus officinalis and Olea europaea, are rich in bioactive compounds that represent most of the phenolic compounds' families and have exhibited potential benefits in human health. These plants have been used in folk medicine for their potential therapeutic properties in human chronic diseases. Recent evidence leads to postulate that polyphenols may account for such effects. Nevertheless, the compounds or metabolites that are responsible for reaching the molecular targets are unknown. data based on studies directly using complex extracts on cellular models, without considering metabolic aspects, have limited applicability. In contrast, studies exploring the absorption process, metabolites in the blood circulation and tissues have become essential to identify the intracellular final effectors that are responsible for extracts bioactivity. Once the cellular metabolites are identified using high-resolution mass spectrometry, docking techniques suppose a unique tool for virtually screening a large number of compounds on selected targets in order to elucidate their potential mechanisms. we provide an updated overview of the in vitro and in vivo studies on the toxicity, absorption, permeability, pharmacokinetics and cellular metabolism of bioactive compounds derived from the abovementioned plants to identify the potential compounds that are responsible for the observed health effects. we propose the use of targeted metabolomics followed by in silico studies to virtually screen identified metabolites on selected protein targets, in combination with the use of the candidate metabolites in cellular models, as the methods of choice for elucidating the molecular mechanisms of these compounds. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Transcriptional profiling reveals elevated Sox2 in DNA polymerase ß null mouse embryonic fibroblasts

PubMed Central

Li, Jianfeng; Luthra, Soumya; Wang, Xiao-Hong; Chandran, Uma R; Sobol, Robert W

2012-01-01

There are over 150 human proteins that have been categorized as bona fide DNA repair proteins. These DNA repair proteins maintain the integrity of the genome, reducing the onset of cancer, disease and aging phenotypes. Variations in expression and/or function would therefore impact genome integrity as well as the cellular response to genotoxins. Global gene expression analysis is an effective approach to uncover defects in DNA repair gene expression and to discover cellular and/or organismal effects brought about by external stimuli such as environmental genotoxicants, chemotherapeutic regimens, viral infections as well as developmental and age-related stimuli. Given the significance of genome stability in cell survival and response to stimuli, we have hypothesized that cells may undergo transcriptional re-programming to accommodate defects in basal DNA repair capacity to promote survival. As a test of this hypothesis, we have compared the transcriptome in three DNA polymerase ß knockout (Polß-KO) mouse embryonic fibroblasts (MEFs) and the corresponding wild-type (WT) littermate control cell lines. Each Polß-KO cell line was found to have a range of genes up-regulated, when compared to its WT littermate control cell line. Interestingly, six (6) genes were commonly up regulated in all three Polß-KO cell lines, including Sox2, one of several genes associated with the induction of pluripotent stem cells. Herein, we present these findings and suggest that loss of DNA repair and the induction of cellular transcriptional re-programming may, in part, contribute to tumor formation and the cellular response to external stimuli. PMID:23226616

Mannosylated Mucin-Type Immunoglobulin Fusion Proteins Enhance Antigen-Specific Antibody and T Lymphocyte Responses

PubMed Central

Johansson, Tomas; Nilsson, Anki; Chatzissavidou, Nathalie; Sjöblom, Magnus; Rova, Ulrika; Holgersson, Jan

2012-01-01

Targeting antigens to antigen-presenting cells (APC) improve their immunogenicity and capacity to induce Th1 responses and cytotoxic T lymphocytes (CTL). We have generated a mucin-type immunoglobulin fusion protein (PSGL-1/mIgG2b), which upon expression in the yeast Pichia pastoris became multivalently substituted with O-linked oligomannose structures and bound the macrophage mannose receptor (MMR) and dendritic cell-specific intercellular adhesion molecule-3 grabbing non-integrin (DC-SIGN) with high affinity in vitro. Here, its effects on the humoral and cellular anti-ovalbumin (OVA) responses in C57BL/6 mice are presented. OVA antibody class and subclass responses were determined by ELISA, the generation of anti-OVA CTLs was assessed in 51Cr release assays using in vitro-stimulated immune spleen cells from the different groups of mice as effector cells and OVA peptide-fed RMA-S cells as targets, and evaluation of the type of Th cell response was done by IFN-γ, IL-2, IL-4 and IL-5 ELISpot assays. Immunizations with the OVA − mannosylated PSGL-1/mIgG2b conjugate, especially when combined with the AbISCO®-100 adjuvant, lead to faster, stronger and broader (with regard to IgG subclass) OVA IgG responses, a stronger OVA-specific CTL response and stronger Th1 and Th2 responses than if OVA was used alone or together with AbISCO®-100. Also non-covalent mixing of mannosylated PSGL-1/mIgG2b, OVA and AbISCO®-100 lead to relatively stronger humoral and cellular responses. The O-glycan oligomannoses were necessary because PSGL-1/mIgG2b with mono- and disialyl core 1 structures did not have this effect. Mannosylated mucin-type fusion proteins can be used as versatile APC-targeting molecules for vaccines and as such enhance both humoral and cellular immune responses. PMID:23071675

[Evaluation of Cellular Effects Caused by Lunar Regolith Simulant Including Fine Particles].

PubMed

Horie, Masanori; Miki, Takeo; Honma, Yoshiyuki; Aoki, Shigeru; Morimoto, Yasuo

2015-06-01

The National Aeronautics and Space Administration has announced a plan to establish a manned colony on the surface of the moon, and our country, Japan, has declared its participation. The surface of the moon is covered with soil called lunar regolith, which includes fine particles. It is possible that humans will inhale lunar regolith if it is brought into the spaceship. Therefore, an evaluation of the pulmonary effects caused by lunar regolith is important for exploration of the moon. In the present study, we examine the cellular effects of lunar regolith simulant, whose components are similar to those of lunar regolith. We focused on the chemical component and particle size in particular. The regolith simulant was fractionated to < 10 μm, < 25 μm and 10-25 μm by gravitational sedimentation in suspensions. We also examined the cellular effects of fine regolith simulant whose primary particle size is 5.10 μm. These regolith simulants were applied to human lung carcinoma A549 cells at concentrations of 0.1 and 1.0 mg/ml. Cytotoxicity, oxidative stress and immune response were examined after 24 h exposure. Cell membrane damage, mitochondrial dysfunction and induction of Interleukin-8 (IL-8) were observed at the concentration of 1.0 mg/ml. The cellular effects of the regolith simulant at the concentration of 0.1 mg/ml were small, as compared with crystalline silica as a positive control. Secretion of IL-1β and tumor necrosis factor-α (TNF-α) was observed at the concentration of 1.0 mg/ml, but induction of gene expression was not observed at 24 h after exposure. Induction of cellular oxidative stress was small. Although the cellular effects tended to be stronger in the < 10 μm particles, there was no remarkable difference. These results suggest that the chemical components and particle size have little relationship to the cellular effects of lunar regolith simulant such as cell membrane damage, induction of oxidative stress and proinflammatory effect.

Monitoring nanoparticle-mediated cellular hyperthermia with a high-sensitivity biosensor

PubMed Central

Mukherjee, Amarnath; Castanares, Mark; Hedayati, Mohammad; Wabler, Michele; Trock, Bruce; Kulkarni, Prakash; Rodriguez, Ronald; Getzenberg, Robert H; DeWeese, Theodore L; Ivkov, Robert; Lupold, Shawn E

2014-01-01

Aim To develop and apply a heat-responsive and secreted reporter assay for comparing cellular response to nanoparticle (NP)- and macroscopic-mediated sublethal hyperthermia. Materials & methods Reporter cells were heated by water bath (macroscopic heating) or iron oxide NPs activated by alternating magnetic fields (nanoscopic heating). Cellular responses to these thermal stresses were measured in the conditioned media by secreted luciferase assay. Results & conclusion Reporter activity was responsive to macroscopic and nanoparticle heating and activity correlated with measured macroscopic thermal dose. Significant cellular responses were observed with NP heating under doses that were insufficient to measurably change the temperature of the system. Under these conditions, the reporter response correlated with proximity to cells loaded with heated nanoparticles. These results suggest that NP and macroscopic hyperthermia may be distinctive under conditions of mild hyperthermia. PMID:24547783

Multiplexed Nanoplasmonic Temporal Profiling of T-Cell Response under Immunomodulatory Agent Exposure

PubMed Central

2016-01-01

Immunomodulatory drugs—agents regulating the immune response—are commonly used for treating immune system disorders and minimizing graft versus host disease in persons receiving organ transplants. At the cellular level, immunosuppressant drugs are used to inhibit pro-inflammatory or tissue-damaging responses of cells. However, few studies have so far precisely characterized the cellular-level effect of immunomodulatory treatment. The primary challenge arises due to the rapid and transient nature of T-cell immune responses to such treatment. T-cell responses involve a highly interactive network of different types of cytokines, which makes precise monitoring of drug-modulated T-cell response difficult. Here, we present a nanoplasmonic biosensing approach to quantitatively characterize cytokine secretion behaviors of T cells with a fine time-resolution (every 10 min) that are altered by an immunosuppressive drug used in the treatment of T-cell-mediated diseases. With a microfluidic platform integrating antibody-conjugated gold nanorod (AuNR) arrays, the technique enables simultaneous multi-time-point measurements of pro-inflammatory (IL-2, IFN-γ, and TNF-α) and anti-inflammatory (IL-10) cytokines secreted by T cells. The integrated nanoplasmonic biosensors achieve precise measurements with low operating sample volume (1 μL), short assay time (∼30 min), heightened sensitivity (∼20–30 pg/mL), and negligible sensor crosstalk. Data obtained from the multicytokine secretion profiles with high practicality resulting from all of these sensing capabilities provide a comprehensive picture of the time-varying cellular functional state during pharmacologic immunosuppression. The capability to monitor cellular functional response demonstrated in this study has great potential to ultimately permit personalized immunomodulatory treatment. PMID:27478873

Human T-cell leukemia virus-I tax oncoprotein functionally targets a subnuclear complex involved in cellular DNA damage-response.

PubMed

Haoudi, Abdelali; Daniels, Rodney C; Wong, Eric; Kupfer, Gary; Semmes, O John

2003-09-26

The virally encoded oncoprotein Tax has been implicated in HTLV-1-mediated cellular transformation. The exact mechanism by which this protein contributes to the oncogenic process is not known. However, it has been hypothesized that Tax induces genomic instability via repression of cellular DNA repair. We examined the effect of de novo Tax expression upon the cell cycle, because appropriate activation of cell cycle checkpoints is essential to a robust damage-repair response. Upon induction of tax expression, Jurkat T-cells displayed a pronounced accumulation in G2/M that was reversible by caffeine. We examined the G2-specific checkpoint signaling response in these cells and found activation of the ATM/chk2-mediated pathway, whereas the ATR/chk1-mediated response was unaffected. Immunoprecipitation with anti-chk2 antibody results in co-precipitation of Tax demonstrating a direct interaction of Tax with a chk2-containing complex. We also show that Tax targets a discrete nuclear site and co-localizes with chk2 and not chk1. This nuclear site, previously identified as Tax Speckled Structures (TSS), also contains the early damage response factor 53BP1. The recruitment of 53BP1 to TSS is dependent upon ATM signaling and requires expression of Tax. Specifically, Tax expression induces redistribution of diffuse nuclear 53BP1 to the TSS foci. Taken together these data suggest that the TSS describe a unique nuclear site involved in DNA damage recognition, repair response, and cell cycle checkpoint activation. We suggest that association of Tax with this multifunctional subnuclear site results in disruption of a subset of the site-specific activities and contributes to cellular genomic instability.

New approach to modulate retinal cellular toxic effects of high glucose using marine epa and dha.

PubMed

Dutot, Mélody; de la Tourrette, Violaine; Fagon, Roxane; Rat, Patrice

2011-06-16

Protective effects of omega-3 fatty acids against cellular damages of high glucose were studied on retinal pigmented epithelial (RPE) cells. Retinal epithelial cells were incubated with omega-3 marine oils rich in EPA and DHA and then with high glucose (25 mM) for 48 hours. Cellular responses were compared to normal glucose (5 mM): intracellular redox status, reactive oxygen species (ROS), mitochondrial succinate deshydrogenase activity, inflammatory cytokines release and caveolin-1 expression were evaluated using microplate cytometry, ELISA and flow cytometry techniques. Fatty acids incorporation in retinal cell membranes was analysed using chromatography. Preincubation of the cells with fish oil decreased ROS overproduction, mitochondrial alterations and TNFα release. These protective effects could be attributed to an increase in caveolin-1 expression induced by marine oil. Marine formulations rich in omega-3 fatty acids represent a promising therapeutic approach for diabetic retinopathy.

Effect of intratympanic dexamethasone, memantine and piracetam on cellular apoptosis due to cisplatin ototoxicity.

PubMed

Topdag, M; Iseri, M; Gelenli, E; Yardimoglu, M; Yazir, Y; Ulubil, S A; Topdag, D O; Ustundag, E

2012-11-01

This study aimed to contribute to the literature on the prevention and treatment of ototoxicity due to various drugs and chemicals. This study compared the histological effects of intratympanic dexamethasone, memantine and piracetam on cellular apoptosis due to cisplatin ototoxicity, in 36 rats. Dexamethasone and memantine had significant effects on the stria vascularis, organ of Corti and spiral ganglion (p < 0.05). Although piracetam decreased the apoptosis rate, this effect was not statistically significant (p > 0.05). Dexamethasone and memantine were found superior to piracetam in reducing apoptosis due to cisplatin ototoxicity. Further studies of this subject are needed, incorporating electron microscopy and auditory brainstem response testing.

Bacteroides Fragilis OmpA: Utility as a Live Vaccine Vector for Biodefense Agents

DTIC Science & Technology

2008-01-01

of handling diseases in large populations. Studies of the immune system and vaccine effectiveness have shown that the ideal way to induce a...the past 15 years, experimental bacterial vaccine vectors have been produced that elicit immune responses against bacterial, viral, protozoan and...given orally, and they can be treated with antibiotics if desired and they effectively induce both humoral and cellular responses. If the organism

Effects of Cetuximab and Erlotinib on the behaviour of cancer stem cells in head and neck squamous cell carcinoma.

PubMed

Setúbal Destro Rodrigues, Maria Fernanda; Gammon, Luke; Rahman, Muhammad M; Biddle, Adrian; Nunes, Fabio Daumas; Mackenzie, Ian C

2018-03-02

The therapeutic responses of many solid tumours to chemo- and radio-therapies are far from fully effective but therapies targeting malignancy-related cellular changes show promise for further control. In head and neck squamous cell carcinoma, the epidermal growth factor receptor (EGFR) is commonly overexpressed and investigation of agents that block this receptor indicate a limited response when used alone but an ability to enhance the actions of other drugs. The hierarchical stem cell patterns present in tumours generate cellular heterogeneity and this is further complicated by cancer stem cells (CSC) shifting between epithelial (Epi-CSC) and mesenchymal (EMT-CSC) states. To clarify how such heterogeneity influences responses to EGFR blocking, we examined the effects of Cetuximab and Erlotinib on the cell sub-populations in HNSCC cell lines. These agents reduced cell proliferation for all subpopulations but induced little cell death. They did however induce large shifts of cells between the EMT-CSC, Epi-CSC and differentiating cell compartments. Loss of EMT-CSCs reduced cell motility and is expected to reduce invasion and metastasis. EGFR blocking also induced shifts of Epi-CSCs into the differentiating cell compartment which typically has greater sensitivity to chemo/radiation, an effect expected to enhance the overall response of tumour cell populations to adjunctive therapies.

Effects of Cetuximab and Erlotinib on the behaviour of cancer stem cells in head and neck squamous cell carcinoma

PubMed Central

Setúbal Destro Rodrigues, Maria Fernanda; Gammon, Luke; Rahman, Muhammad M.; Biddle, Adrian; Nunes, Fabio Daumas; Mackenzie, Ian C.

2018-01-01

The therapeutic responses of many solid tumours to chemo- and radio-therapies are far from fully effective but therapies targeting malignancy-related cellular changes show promise for further control. In head and neck squamous cell carcinoma, the epidermal growth factor receptor (EGFR) is commonly overexpressed and investigation of agents that block this receptor indicate a limited response when used alone but an ability to enhance the actions of other drugs. The hierarchical stem cell patterns present in tumours generate cellular heterogeneity and this is further complicated by cancer stem cells (CSC) shifting between epithelial (Epi-CSC) and mesenchymal (EMT-CSC) states. To clarify how such heterogeneity influences responses to EGFR blocking, we examined the effects of Cetuximab and Erlotinib on the cell sub-populations in HNSCC cell lines. These agents reduced cell proliferation for all subpopulations but induced little cell death. They did however induce large shifts of cells between the EMT-CSC, Epi-CSC and differentiating cell compartments. Loss of EMT-CSCs reduced cell motility and is expected to reduce invasion and metastasis. EGFR blocking also induced shifts of Epi-CSCs into the differentiating cell compartment which typically has greater sensitivity to chemo/radiation, an effect expected to enhance the overall response of tumour cell populations to adjunctive therapies. PMID:29568372

Phosphoprotein profiles of candidate markers for early cellular responses to low-dose γ-radiation in normal human fibroblast cells

PubMed Central

Yim, Ji-Hye; Yun, Jung Mi; Kim, Ji Young; Lee, In Kyung; Nam, Seon Young

2017-01-01

Abstract Ionizing radiation causes biological damage that leads to severe health effects. However, the effects and subsequent health implications caused by exposure to low-dose radiation are unclear. The objective of this study was to determine phosphoprotein profiles in normal human fibroblast cell lines in response to low-dose and high-dose γ-radiation. We examined the cellular response in MRC-5 cells 0.5 h after exposure to 0.05 or 2 Gy. Using 1318 antibodies by antibody array, we observed ≥1.3-fold increases in a number of identified phosphoproteins in cells subjected to low-dose (0.05 Gy) and high-dose (2 Gy) radiation, suggesting that both radiation levels stimulate distinct signaling pathways. Low-dose radiation induced nucleic acid–binding transcription factor activity, developmental processes, and multicellular organismal processes. By contrast, high-dose radiation stimulated apoptotic processes, cell adhesion and regulation, and cellular organization and biogenesis. We found that phospho-BTK (Tyr550) and phospho-Gab2 (Tyr643) protein levels at 0.5 h after treatment were higher in cells subjected to low-dose radiation than in cells treated with high-dose radiation. We also determined that the phosphorylation of BTK and Gab2 in response to ionizing radiation was regulated in a dose-dependent manner in MRC-5 and NHDF cells. Our study provides new insights into the biological responses to low-dose γ-radiation and identifies potential candidate markers for monitoring exposure to low-dose ionizing radiation. PMID:28122968

Triclosan Induces Thymic Stromal Lymphopoietin in Skin Promoting Th2 Allergic Responses

PubMed Central

Marshall, Nikki B.; Lukomska, Ewa; Long, Carrie M.; Kashon, Michael L.; Sharpnack, Douglas D.; Nayak, Ajay P.; Anderson, Katie L.; Meade, B. Jean; Anderson, Stacey E.

2016-01-01

Triclosan is an antimicrobial chemical incorporated into many personal, medical and household products. Approximately, 75% of the U.S. population has detectable levels of triclosan in their urine, and although it is not typically considered a contact sensitizer, recent studies have begun to link triclosan exposure with augmented allergic disease. We examined the effects of dermal triclosan exposure on the skin and lymph nodes of mice and in a human skin model to identify mechanisms for augmenting allergic responses. Triclosan (0%–3%) was applied topically at 24-h intervals to the ear pinnae of OVA-sensitized BALB/c mice. Skin and draining lymph nodes were evaluated for cellular responses and cytokine expression over time. The effects of triclosan (0%–0.75%) on cytokine expression in a human skin tissue model were also examined. Exposure to triclosan increased the expression of TSLP, IL-1β, and TNF-α in the skin with concomitant decreases in IL-25, IL-33, and IL-1α. Similar changes in TSLP, IL1B, and IL33 expression occurred in human skin. Topical application of triclosan also increased draining lymph node cellularity consisting of activated CD86+GL-7+ B cells, CD80+CD86+ dendritic cells, GATA-3+OX-40+IL-4+IL-13+ Th2 cells and IL-17 A+ CD4 T cells. In vivo antibody blockade of TSLP reduced skin irritation, IL-1β expression, lymph node cellularity, and Th2 responses augmented by triclosan. Repeated dermal exposure to triclosan induces TSLP expression in skin tissue as a potential mechanism for augmenting allergic responses. PMID:26048654

47 CFR 22.901 - Cellular service requirements and limitations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.901 Cellular service requirements and limitations. The licensee of each cellular system is responsible for ensuring that its cellular system operates in compliance with this section. (a) Each cellular system must provide either mobile service...

Earlier Detection of Tumor Treatment Response Using Magnetic Resonance Diffusion Imaging with Oscillating Gradients

PubMed Central

Colvin, Daniel C.; Loveless, Mary E.; Does, Mark D.; Yue, Zou; Yankeelov, Thomas E.; Gore, John C.

2011-01-01

An improved method for detecting early changes in tumors in response to treatment, based on a modification of diffusion-weighted magnetic resonance imaging, has been demonstrated in an animal model. Early detection of therapeutic response in tumors is important both clinically and in pre-clinical assessments of novel treatments. Non-invasive imaging methods that can detect and assess tumor response early in the course of treatment, and before frank changes in tumor morphology are evident, are of considerable interest as potential biomarkers of treatment efficacy. Diffusion-weighted magnetic resonance imaging is sensitive to changes in water diffusion rates in tissues that result from structural variations in the local cellular environment, but conventional methods mainly reflect changes in tissue cellularity and do not convey information specific to micro-structural variations at sub-cellular scales. We implemented a modified imaging technique using oscillating gradients of the magnetic field for evaluating water diffusion rates over very short spatial scales that are more specific for detecting changes in intracellular structure that may precede changes in cellularity. Results from a study of orthotopic 9L gliomas in rat brains indicate that this method can detect changes as early as 24 hours following treatment with 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU), when conventional approaches do not find significant effects. These studies suggest that diffusion imaging using oscillating gradients may be used to obtain an earlier indication of treatment efficacy than previous magnetic resonance imaging methods. PMID:21190804

Effects of Spaceflight on Molecular and Cellular Responses to Bleomycin-induced DNA Damages in Confluent Human Fibroblasts

NASA Astrophysics Data System (ADS)

Lu, Tao; Wu, Honglu; Karouia, Fathi; Stodieck, Louis; Zhang, Ye; Wong, Michael

2016-07-01

Spaceflights expose human beings to various risk factors. Among them are microgravity related physiological stresses in immune, cytoskeletal, and cardiovascular systems, and space radiation related elevation of cancer risk. Cosmic radiation consists of energetic protons and other heavier charged particles that induce DNA damages. Effective DNA damage response and repair mechanism is important to maintain genomic integrity and reduce cancer risk. There were studies on effects of spaceflight and microgravity on DNA damage response in cell and animal models, but the published results were mostly conflicting and inconsistent. To investigate effects of spaceflight on molecular and cellular responses to DNA damages, bleomycin, an anti-cancer drug and radiomimetic reagent, was used to induce DNA damages in confluent human fibroblasts flown to the International Space Station (ISS) and on ground. After exposure to 1.0 mg/ml bleomycin for 3 hours, cells were fixed for immunofluorescence assays and for RNA preparation. Extents of DNA damages were quantified by focus pattern and focus number counting of phosphorylated histone protein H2AX (γg-H2AX). The cells on the ISS showed modestly increased average focus counts per nucleus while the distribution of patterns was similar to that on the ground. PCR array analysis showed that expressions of several genes, including CDKN1A and PCNA, were significantly changed in response to DNA damages induced by bleomycin in both flight and ground control cells. However, there were no significant differences in the overall expression profiles of DNA damage response genes between the flight and ground samples. Analysis of cellular proliferation status with Ki-67 staining showed a slightly higher proliferating population in cells on the ISS than those on ground. Our results suggested that the difference in γg-H2AX focus counts between flight and ground was due to the higher percentage of proliferating cells in space, but spaceflight did not significantly affect initial transcriptional responses to bleomycin treatment in the selected genes in the DNA damage signaling pathways.

Silica nanoparticles are less toxic to human lung cells when deposited at the air–liquid interface compared to conventional submerged exposure

PubMed Central

Saathoff, Harald; Leisner, Thomas; Al-Rawi, Marco; Simon, Michael; Seemann, Gunnar; Dössel, Olaf; Mülhopt, Sonja; Paur, Hanns-Rudolf; Fritsch-Decker, Susanne

2014-01-01

Summary Background: Investigations on adverse biological effects of nanoparticles (NPs) in the lung by in vitro studies are usually performed under submerged conditions where NPs are suspended in cell culture media. However, the behaviour of nanoparticles such as agglomeration and sedimentation in such complex suspensions is difficult to control and hence the deposited cellular dose often remains unknown. Moreover, the cellular responses to NPs under submerged culture conditions might differ from those observed at physiological settings at the air–liquid interface. Results: In order to avoid problems because of an altered behaviour of the nanoparticles in cell culture medium and to mimic a more realistic situation relevant for inhalation, human A549 lung epithelial cells were exposed to aerosols at the air–liquid interphase (ALI) by using the ALI deposition apparatus (ALIDA). The application of an electrostatic field allowed for particle deposition efficiencies that were higher by a factor of more than 20 compared to the unmodified VITROCELL deposition system. We studied two different amorphous silica nanoparticles (particles produced by flame synthesis and particles produced in suspension by the Stöber method). Aerosols with well-defined particle sizes and concentrations were generated by using a commercial electrospray generator or an atomizer. Only the electrospray method allowed for the generation of an aerosol containing monodisperse NPs. However, the deposited mass and surface dose of the particles was too low to induce cellular responses. Therefore, we generated the aerosol with an atomizer which supplied agglomerates and thus allowed a particle deposition with a three orders of magnitude higher mass and of surface doses on lung cells that induced significant biological effects. The deposited dose was estimated and independently validated by measurements using either transmission electron microscopy or, in case of labelled NPs, by fluorescence analyses. Surprisingly, cells exposed at the ALI were less sensitive to silica NPs as evidenced by reduced cytotoxicity and inflammatory responses. Conclusion: Amorphous silica NPs induced qualitatively similar cellular responses under submerged conditions and at the ALI. However, submerged exposure to NPs triggers stronger effects at much lower cellular doses. Hence, more studies are warranted to decipher whether cells at the ALI are in general less vulnerable to NPs or specific NPs show different activities dependent on the exposure method. PMID:25247141

The importance of the cellular stress response in the pathogenesis and treatment of type 2 diabetes.

PubMed

Hooper, Philip L; Balogh, Gabor; Rivas, Eric; Kavanagh, Kylie; Vigh, Laszlo

2014-07-01

Organisms have evolved to survive rigorous environments and are not prepared to thrive in a world of caloric excess and sedentary behavior. A realization that physical exercise (or lack of it) plays a pivotal role in both the pathogenesis and therapy of type 2 diabetes mellitus (t2DM) has led to the provocative concept of therapeutic exercise mimetics. A decade ago, we attempted to simulate the beneficial effects of exercise by treating t2DM patients with 3 weeks of daily hyperthermia, induced by hot tub immersion. The short-term intervention had remarkable success, with a 1 % drop in HbA1, a trend toward weight loss, and improvement in diabetic neuropathic symptoms. An explanation for the beneficial effects of exercise and hyperthermia centers upon their ability to induce the cellular stress response (the heat shock response) and restore cellular homeostasis. Impaired stress response precedes major metabolic defects associated with t2DM and may be a near seminal event in the pathogenesis of the disease, tipping the balance from health into disease. Heat shock protein inducers share metabolic pathways associated with exercise with activation of AMPK, PGC1-a, and sirtuins. Diabetic therapies that induce the stress response, whether via heat, bioactive compounds, or genetic manipulation, improve or prevent all of the morbidities and comorbidities associated with the disease. The agents reduce insulin resistance, inflammatory cytokines, visceral adiposity, and body weight while increasing mitochondrial activity, normalizing membrane structure and lipid composition, and preserving organ function. Therapies restoring the stress response can re-tip the balance from disease into health and address the multifaceted defects associated with the disease.

Stressed to death: implication of lymphocyte apoptosis for psychoneuroimmunology

NASA Technical Reports Server (NTRS)

Shi, Yufang; Devadas, Satish; Greeneltch, Kristy M.; Yin, Deling; Allan Mufson, R.; Zhou, Jian-nian

2003-01-01

Psychological and physical stressors best exemplify the intercommunication of the immune and the nervous systems. It has been shown that stress significantly impacts leukocyte cellularity and immune responses and alters susceptibility to various diseases. While acute stress has been shown to enhance immune responses, chronic stress often leads to immunosuppression. Among many criteria examined upon exposure to chronic stress, the reduction in lymphocyte mitogenic response and lymphocyte cellularity are commonly assessed. We have reported that chronic restraint stress could induce lymphocyte reduction, an effect dependent on endogenous opioids. Interestingly, the effect of endogenous opioids was found to be exerted through increasing the expression of a cell death receptor, Fas, and an increased sensitivity of lymphocytes to apoptosis. Stress-induced lymphocyte reduction was not affected by adrenalectomy. In this review, based on available literature and our recent data, we will discuss the role of the hypothalamic-pituitary-adrenal axis and endogenous opioids and examine the mechanisms by which chronic stress modulates lymphocyte apoptosis.

Testisimmune privilege - Assumptions versus facts

PubMed Central

Kaur, G.; Mital, P.; Dufour, J.M.

2013-01-01

The testis has long enjoyed a reputation as an immunologically privileged site based on its ability to protect auto-antigenic germ cells and provide an optimal environment for the extended survival of transplanted allo- or xeno-grafts. Exploration of the role of anatomical, physiological, immunological and cellular components in testis immune privilege revealed that the tolerogenic environment of the testis is a result of the immunomodulatory factors expressed or secreted by testicular cells (mainly Sertoli cells, peritubular myoid cells, Leydig cells, and resident macrophages). The blood-testis barrier/Sertoli cell barrier, is also important to seclude advanced germ cells but its requirement in testis immune privilege needs further investigation. Testicular immune privilege is not permanent, as an effective immune response can be mounted against transplanted tissue, and bacterial/viral infections in the testis can be effectively eliminated. Overall, the cellular components control the fate of the immune response and can shift the response from immunodestructive to immunoprotective, resulting in immune privilege. PMID:25309630

Cellular responses to nicotinic receptor activation are decreased after prolonged exposure to galantamine in human neuroblastoma cells.

PubMed

Barik, Jacques; Dajas-Bailador, Federico; Wonnacott, Susan

2005-08-01

In this study, we have examined cellular responses of neuroblastoma SH-SY5Y cells after chronic treatment with galantamine, a drug used to treat Alzheimer's disease that has a dual mechanism of action: inhibition of acetylcholinesterase and allosteric potentiation of nicotinic acetylcholine receptors (nAChR). Acute experiments confirmed that maximum potentiation of nicotinic responses occurs at 1 microM galantamine; hence this concentration was chosen for chronic treatment. Exposure to 1 microM galantamine for 4 days decreased Ca(2+) responses (by 19.8+/-3.6%) or [(3)H]noradrenaline ([(3)H]NA) release (by 23.9+/-3.3%) elicited by acute application of nicotine. KCl-evoked increases in intracellular Ca(2+) were also inhibited by 10.0+/-1.9% after 4 days' treatment with galantamine. These diminished responses are consistent with the downregulation of downstream cellular processes. Ca(2+) responses evoked by activation of muscarinic acetylcholine receptors were unaffected by chronic galantamine treatment. Exposure to the more potent acetylcholinesterase inhibitor rivastigmine (1 microM) for 4 days failed to alter nicotine-, KCl-, or muscarinic receptor-evoked increases in intracellular Ca(2+). These observations support the hypothesis that chronic galantamine exerts its effects through interaction with nAChR in this cell line. Exposure to 10 microM nicotine for 4 days produced decreases in acute nicotine- (18.0+/-3.5%) and KCl-evoked Ca(2+) responses (10.6+/-2.5%) and nicotine-evoked [(3)H]NA release (26.0+/-3.3%) that are comparable to the effects of a corresponding exposure to galantamine. Treatment with 1 microM galantamine did not alter numbers of [(3)H]epibatidine-binding sites in SH-SY5Y cells, in contrast to 62% upregulation of these sites in response to 10 microM nicotine. Thus, chronic galantamine acts at nAChR to decrease subsequent functional responses to acute stimulation with nicotine or KCl. This effect appears to be independent of the upregulation of nAChR-binding sites.

Enhanced Medial Collateral Ligament Healing using Mesenchymal Stem Cells: Dosage Effects on Cellular Response and Cytokine Profile

PubMed Central

Saether, Erin E.; Chamberlain, Connie S.; Leiferman, Ellen M.; Kondratko-Mittnacht, Jaclyn R.; Li, Wan Ju; Brickson, Stacey L.; Vanderby, Ray

2013-01-01

Mesenchymal stem cells (MSCs) have potential therapeutic applications for musculoskeletal injuries due to their ability to differentiate into several tissue cell types and modulate immune and inflammatory responses. These immune-modulatory properties were examined in vivo during early stage rat medial collateral ligament healing. Two different cell doses (low dose 1×106 or high dose 4×106 MSCs) were administered at the time of injury and compared with normal ligament healing at days 5 and 14 post-injury. At both times, the high dose MSC group demonstrated a significant decrease in M2 macrophages compared to controls. At day 14, fewer M1 macrophages were detected in the low dose group compared to the high dose group. These results, along with significant changes in procollagen I, proliferating cells, and endothelialization suggest that MSCs can alter the cellular response during healing in a dose-dependent manner. The higher dose ligaments also had increased expression of several pro-inflammatory cytokines at day 5 (IL-1β, IFNγ, IL-2) and increased expression of IL-12 at day 14. Mechanical testing at day 14 revealed increased failure strength and stiffness in low dose ligaments compared to controls. Based on these improved mechanical properties, MSCs enhanced functional healing when applied at a lower dose. Different doses of MSCs uniquely affected the cellular response and cytokine expression in healing ligaments. Interestingly, the lower dose of cells proved to be most effective in improving functional properties. PMID:24174129

Phototoxic effects of free phthalocyanine and phthalocyanine conjugated to gold nanoparticles for targeted photodynamic therapy of melanoma cancer

NASA Astrophysics Data System (ADS)

Manoto, Sello L.; Oluwole, David O.; Malabi, Rudzani; Maphanga, Charles; Ombinda-Lemboumba, Saturnin; Nyokong, Tebello; Mthunzi-Kufa, Patience

2017-02-01

Photodynamic therapy (PDT) has emerged as an effective treatment modality for various malignant neoplasia and diseases. In PDT, the photochemical interaction of photosensitizer (PS), light and molecular oxygen produces singlet oxygen which can lead to tumour cell apoptosis, necrosis or autophagy. The success of PDT is limited by the hydrophobic characteristic of the PS which hinders treatment administration and efficiency. To circumvent this limitation, PS can be incorporated in nanostructured drug delivery systems such as gold nanoparticles (AuNPs). In this study, we investigated the effectiveness of free zinc monocarboxyphenoxy phthalocyanine (ZnMCPPc) and ZnMCPPc conjugated to AuNPs. Commercially purchased melanoma cancer cells cultured as cell monolayers were used in this study. Changes in cellular response were evaluated using cellular morphology, viability, proliferation and cytotoxicity. Untreated cells showed no changes in cellular morphology, proliferation and cytotoxicity. However, photoactivated free ZnMCPPc and ZnMCPPc conjugated to AuNPs showed changes in cellular morphology and a dose dependent decrease in cellular viability and proliferation as well as an increase in cell membrane. ZnMCPPc conjugated to AuNPs showed an improved efficiency in PDT as compared to free ZnMCPPc, which might be as a result of the vehicle effect of AuNPs. Both PSs used in this study were effective in inducing cell death with ZnMCPPc conjugated to AuNPs showing great potential as an effective PS for PDT.

Silymarin Suppresses Cellular Inflammation By Inducing Reparative Stress Signaling.

PubMed

Lovelace, Erica S; Wagoner, Jessica; MacDonald, James; Bammler, Theo; Bruckner, Jacob; Brownell, Jessica; Beyer, Richard P; Zink, Erika M; Kim, Young-Mo; Kyle, Jennifer E; Webb-Robertson, Bobbie-Jo M; Waters, Katrina M; Metz, Thomas O; Farin, Federico; Oberlies, Nicholas H; Polyak, Stephen J

2015-08-28

Silymarin, a characterized extract of the seeds of milk thistle (Silybum marianum), suppresses cellular inflammation. To define how this occurs, transcriptional profiling, metabolomics, and signaling studies were performed in human liver and T cell lines. Cellular stress and metabolic pathways were modulated within 4 h of silymarin treatment: activation of Activating Transcription Factor 4 (ATF-4) and adenosine monophosphate protein kinase (AMPK) and inhibition of mammalian target of rapamycin (mTOR) signaling, the latter being associated with induction of DNA-damage-inducible transcript 4 (DDIT4). Metabolomics analyses revealed silymarin suppression of glycolytic, tricarboxylic acid (TCA) cycle, and amino acid metabolism. Anti-inflammatory effects arose with prolonged (i.e., 24 h) silymarin exposure, with suppression of multiple pro-inflammatory mRNAs and signaling pathways including nuclear factor kappa B (NF-κB) and forkhead box O (FOXO). Studies with murine knock out cells revealed that silymarin inhibition of both mTOR and NF-κB was partially AMPK dependent, whereas silymarin inhibition of mTOR required DDIT4. Other natural products induced similar stress responses, which correlated with their ability to suppress inflammation. Thus, natural products activate stress and repair responses that culminate in an anti-inflammatory cellular phenotype. Natural products like silymarin may be useful as tools to define how metabolic, stress, and repair pathways regulate cellular inflammation.

Silymarin Suppresses Cellular Inflammation By Inducing Reparative Stress Signaling

PubMed Central

Lovelace, Erica S.; Wagoner, Jessica; MacDonald, James; Bammler, Theo; Bruckner, Jacob; Brownell, Jessica; Beyer, Richard; Zink, Erika M.; Kim, Young-Mo; Kyle, Jennifer E.; Webb-Robertson, Bobbie-Jo; Waters, Katrina M.; Metz, Thomas O.; Farin, Federico; Oberlies, Nicholas H.; Polyak, Stephen J.

2016-01-01

Silymarin, a characterized extract of the seeds of milk thistle (Silybum marianum), suppresses cellular inflammation. To define how this occurs, transcriptional profiling, metabolomics, and signaling studies were performed in human liver and T cell lines. Cellular stress and metabolic pathways were modulated within 4 h of silymarin treatment: activation of Activating Transcription Factor 4 (ATF-4) and adenosine monophosphate protein kinase (AMPK) and inhibition of mammalian target of rapamycin (mTOR) signaling, the latter being associated with induction of DNA-damage-inducible transcript 4 (DDIT4). Metabolomics analyses revealed silymarin suppression of glycolytic, tricarboxylic acid (TCA) cycle, and amino acid metabolism. Anti-inflammatory effects arose with prolonged (i.e. 24 h) silymarin exposure, with suppression of multiple pro-inflammatory mRNAs and signaling pathways including nuclear factor kappa B (NF-κB) and forkhead box O (FOXO). Studies with murine knock out cells revealed that silymarin inhibition of both mTOR and NF-κB was partially AMPK dependent, while silymarin inhibition of mTOR required DDIT4. Other natural products induced similar stress responses, which correlated with their ability to suppress inflammation. Thus, natural products activate stress and repair responses that culminate in an anti-inflammatory cellular phenotype. Natural products like silymarin may be useful as tools to define how metabolic, stress, and repair pathways regulate cellular inflammation. PMID:26186142

Subcutaneous administration CpG-ODNs acts as a potent adjuvant for an HIV-1-tat-based vaccine candidate to elicit cellular immunity in BALB/c mice.

PubMed

Panahi, Zeinab; Abdoli, Asghar; Mosayebi, Ghasem; Mahdavi, Mehdi; Bahrami, Fariborz

2018-03-01

To evaluate the combined effects of CpG oligodeoxynucleotides (CpG-ODNs) adjuvant and subcutaneous injection route on efficacy of a HIV-1-tat DNA vaccine candidate using BALB/c mice as an animal model. Evaluation of cellular and humoral immunity of mice injected subcutaneously with HIV-1-tat gene cloned into a pcDNA3.1 vector indicated that significant levels of IFN-γ cytokine secretion (900 pg/ml), lymphocyte proliferation (2.5 stimulation index) and IgG 2a (1.45 absorbance 450 nm) production could be achieved. These indicators of stimulated cellular immunity were elicited 2 weeks after the last injection (P < 0.05). Formulation of HIV-1-tat DNA vaccine candidate with CpG-ODNs as an adjuvant while administrated subcutaneously are a promising approach to induce effective cellular immunity responses against HIV-1 infection.

Frequent cellular phone use modifies hypothalamic-pituitary-adrenal axis response to a cellular phone call after mental stress in healthy children and adolescents: A pilot study.

PubMed

Geronikolou, Styliani A; Chamakou, Aikaterini; Mantzou, Aimilia; Chrousos, George; KanakaGantenbein, Christina

2015-12-01

The hypothalamic-pituitary-adrenal (HPA) axis is the main "gate-keeper" of the organism's response to every somatic or mental stress. This prospective study aims to investigate the HPA-axis response to a cellular phone call exposure after mental stress in healthy children and adolescents and to assess the possible predictive role of baseline endocrine markers to this response. Two groups of healthy school-age children aged 11-14 (12.5±1.5) years were included in the study, the one comprising those who are occasional users of a cellular phone (Group A) while the second those who do regularly use one (Group B). Blood samples were obtained from all participants at 8.00 am after a 12-hour overnight fasting for thyroid hormone, glucose, insulin, and cortisol levels determination. The participants performed the Trier Social Stress Test for Children (TSST-C) (5 minoral task followed by 5 min arithmetic task). Salivary cortisol samples were obtained at baseline, 10' and 20' min after the TSST-C and 10' and 20' after a 5 minute cellular phone call. Significant changes in the salivary cortisol levels were noted between 10' and 20' mins after the cellular phone call with different responses between the two groups. Baseline thyroid hormone levels seem to predict the cortisol response to mental stress mainly in group A, while HOMA had no impact on salivary cortisol response at any phase of the test, in either group. HPA axis response to cellular phone after mental stress in children and adolescents follow a different pattern in frequent users than in occasional users that seems to be influenced by the baseline thyroid hormone levels. Copyright © 2015 Elsevier B.V. All rights reserved.

Using ToxCast data to reconstruct dynamic cell state ...

EPA Pesticide Factsheets

AbstractBackground. High-throughput in vitro screening is an important tool for evaluating the potential biological activity of the thousands of existing chemicals in commerce and the hundreds more introduced each year. Among the assay technologies available, high-content imaging (HCI) allows multiplexed measurements of cellular phenotypic changes induced by chemical exposures. For a large chemical inventory having limited concentration-time series data, the deconvolution of cellular response profiles into transitive or irrevocable state trajectories is an important consideration. Objectives. Our goal was to analyze temporal and concentration-related cellular changes measured using HCI to identify the “tipping point” at which the cells did not show recovery towards a normal phenotypic state. Methods. The effects of 976 chemicals (ToxCast Phase I and II) were evaluated using HCI as a function of concentration and time in HepG2 cells over a 72-hr exposure period to concentrations ranging from 0.4- to 200 µM. The cellular endpoints included nuclear p53 accumulation, JNK, markers of oxidative stress, cytoskeletal changes, mitochondrial energization and density, cell viability and cell cycle progression. A novel computational model was developed to interpret dynamic multidimensional system responses as cell-state trajectories. Results. Analysis of cell-state trajectories showed that HepG2 cells were resilient to the effects of 178 chemicals up to the highest co

Proteomic profiling reveals DNA damage, nucleolar and ribosomal stress are the main responses to oxaliplatin treatment in cancer cells.

PubMed

Ozdian, Tomas; Holub, Dusan; Maceckova, Zuzana; Varanasi, Lakshman; Rylova, Gabriela; Rehulka, Jiri; Vaclavkova, Jana; Slavik, Hanus; Moudry, Pavel; Znojek, Pawel; Stankova, Jarmila; de Sanctis, Juan Bautista; Hajduch, Marian; Dzubak, Petr

2017-06-06

Oxaliplatin is widely used to treat colorectal cancer in both palliative and adjuvant settings. It is also being tested for use in treating hematological, esophageal, biliary tract, pancreatic, gastric, and hepatocellular cancers. Despite its routine clinical use, little is known about the responses it induces in cancer cells. Therefore the whole-cell proteomics study was conducted to characterize the cellular response induced by oxaliplatin. Chemosensitive CCRF-CEM cells were treated with oxaliplatin at 29.3μM (5×IC 50 ) for 240min (half-time to caspase activation). The proteomes of un-/treated cells were then compared by high-resolution mass spectrometry, revealing 4049 proteins expressed over 3 biological replicates. Among these proteins, 76 were significantly downregulated and 31 significantly upregulated in at least two replicates. In agreement with the DNA-damaging effects of platinum drugs, proteins involved in DNA damage responses were present in both the upregulated and downregulated groups. The downregulated proteins were divided into three subgroups; i) centrosomal proteins, ii) RNA processing and iii) ribosomal proteins, which indicates nucleolar and ribosomal stress. In conclusion, our data supported by further validation experiments indicate the initial cellular response to oxaliplatin is the activation of DNA damage response, which in turn or in parallel triggers nucleolar and ribosomal stress. We have performed a whole-cell proteomic study of cellular response to oxaliplatin treatment, which is the drug predominantly used in the treatment of colorectal cancer. Compared to its predecessors, cisplatin and carboplatin, there is only a small fraction of studies dedicated to oxaliplatin. From those studies, most of them are focused on modification of treatment regimens or study of oxaliplatin in new cancer diagnoses. Cellular response hasn't been studied deeply and to our best knowledge, this is the first whole-cell proteomics study focused exclusively to this important topic, which can help to understand molecular mechanisms of action. Copyright © 2017 Elsevier B.V. All rights reserved.

Mitochondria, Energetics, Epigenetics, and Cellular Responses to Stress

PubMed Central

McAllister, Kimberly; Worth, Leroy; Haugen, Astrid C.; Meyer, Joel N.; Domann, Frederick E.; Van Houten, Bennett; Mostoslavsky, Raul; Bultman, Scott J.; Baccarelli, Andrea A.; Begley, Thomas J.; Sobol, Robert W.; Hirschey, Matthew D.; Ideker, Trey; Santos, Janine H.; Copeland, William C.; Tice, Raymond R.; Balshaw, David M.; Tyson, Frederick L.

2014-01-01

Background: Cells respond to environmental stressors through several key pathways, including response to reactive oxygen species (ROS), nutrient and ATP sensing, DNA damage response (DDR), and epigenetic alterations. Mitochondria play a central role in these pathways not only through energetics and ATP production but also through metabolites generated in the tricarboxylic acid cycle, as well as mitochondria–nuclear signaling related to mitochondria morphology, biogenesis, fission/fusion, mitophagy, apoptosis, and epigenetic regulation. Objectives: We investigated the concept of bidirectional interactions between mitochondria and cellular pathways in response to environmental stress with a focus on epigenetic regulation, and we examined DNA repair and DDR pathways as examples of biological processes that respond to exogenous insults through changes in homeostasis and altered mitochondrial function. Methods: The National Institute of Environmental Health Sciences sponsored the Workshop on Mitochondria, Energetics, Epigenetics, Environment, and DNA Damage Response on 25–26 March 2013. Here, we summarize key points and ideas emerging from this meeting. Discussion: A more comprehensive understanding of signaling mechanisms (cross-talk) between the mitochondria and nucleus is central to elucidating the integration of mitochondrial functions with other cellular response pathways in modulating the effects of environmental agents. Recent studies have highlighted the importance of mitochondrial functions in epigenetic regulation and DDR with environmental stress. Development and application of novel technologies, enhanced experimental models, and a systems-type research approach will help to discern how environmentally induced mitochondrial dysfunction affects key mechanistic pathways. Conclusions: Understanding mitochondria–cell signaling will provide insight into individual responses to environmental hazards, improving prediction of hazard and susceptibility to environmental stressors. Citation: Shaughnessy DT, McAllister K, Worth L, Haugen AC, Meyer JN, Domann FE, Van Houten B, Mostoslavsky R, Bultman SJ, Baccarelli AA, Begley TJ, Sobol RW, Hirschey MD, Ideker T, Santos JH, Copeland WC, Tice RR, Balshaw DM, Tyson FL. 2014. Mitochondria, energetics, epigenetics, and cellular responses to stress. Environ Health Perspect 122:1271–1278; http://dx.doi.org/10.1289/ehp.1408418 PMID:25127496

Boosting BCG-primed responses with a subunit Apa vaccine during the waning phase improves immunity and imparts protection against Mycobacterium tuberculosis.

PubMed

Nandakumar, Subhadra; Kannanganat, Sunil; Dobos, Karen M; Lucas, Megan; Spencer, John S; Amara, Rama Rao; Plikaytis, Bonnie B; Posey, James E; Sable, Suraj B

2016-05-13

Heterologous prime-boosting has emerged as a powerful vaccination approach against tuberculosis. However, optimal timing to boost BCG-immunity using subunit vaccines remains unclear in clinical trials. Here, we followed the adhesin Apa-specific T-cell responses in BCG-primed mice and investigated its BCG-booster potential. The Apa-specific T-cell response peaked 32-52 weeks after parenteral or mucosal BCG-priming but waned significantly by 78 weeks. A subunit-Apa-boost during the contraction-phase of BCG-response had a greater effect on the magnitude and functional quality of specific cellular and humoral responses compared to a boost at the peak of BCG-response. The cellular response increased following mucosal BCG-prime-Apa-subunit-boost strategy compared to Apa-subunit-prime-BCG-boost approach. However, parenteral BCG-prime-Apa-subunit-boost by a homologous route was the most effective strategy in-terms of enhancing specific T-cell responses during waning in the lung and spleen. Two Apa-boosters markedly improved waning BCG-immunity and significantly reduced Mycobacterium tuberculosis burdens post-challenge. Our results highlight the challenges of optimization of prime-boost regimens in mice where BCG drives persistent immune-activation and suggest that boosting with a heterologous vaccine may be ideal once the specific persisting effector responses are contracted. Our results have important implications for design of prime-boost regimens against tuberculosis in humans.

Non-monotonic changes in clonogenic cell survival induced by disulphonated aluminum phthalocyanine photodynamic treatment in a human glioma cell line

PubMed Central

2010-01-01

Background Photodynamic therapy (PDT) involves excitation of sensitizer molecules by visible light in the presence of molecular oxygen, thereby generating reactive oxygen species (ROS) through electron/energy transfer processes. The ROS, thus produced can cause damage to both the structure and the function of the cellular constituents resulting in cell death. Our preliminary investigations of dose-response relationships in a human glioma cell line (BMG-1) showed that disulphonated aluminum phthalocyanine (AlPcS2) photodynamically induced loss of cell survival in a concentration dependent manner up to 1 μM, further increases in AlPcS2concentration (>1 μM) were, however, observed to decrease the photodynamic toxicity. Considering the fact that for most photosensitizers only monotonic dose-response (survival) relationships have been reported, this result was unexpected. The present studies were, therefore, undertaken to further investigate the concentration dependent photodynamic effects of AlPcS2. Methods Concentration-dependent cellular uptake, sub-cellular localization, proliferation and photodynamic effects of AlPcS2 were investigated in BMG-1 cells by absorbance and fluorescence measurements, image analysis, cell counting and colony forming assays, flow cytometry and micronuclei formation respectively. Results The cellular uptake as a function of extra-cellular AlPcS2 concentrations was observed to be biphasic. AlPcS2 was distributed throughout the cytoplasm with intense fluorescence in the perinuclear regions at a concentration of 1 μM, while a weak diffuse fluorescence was observed at higher concentrations. A concentration-dependent decrease in cell proliferation with accumulation of cells in G2+M phase was observed after PDT. The response of clonogenic survival after AlPcS2-PDT was non-monotonic with respect to AlPcS2 concentration. Conclusions Based on the results we conclude that concentration-dependent changes in physico-chemical properties of sensitizer such as aggregation may influence intracellular transport and localization of photosensitizer. Consequent modifications in the photodynamic induction of lesions and their repair leading to different modes of cell death may contribute to the observed non-linear effects. PMID:20433757

Epidermal Growth Factor Enhances Cellular Uptake of Polystyrene Nanoparticles by Clathrin-Mediated Endocytosis

PubMed Central

Phuc, Le Thi Minh; Taniguchi, Akiyoshi

2017-01-01

The interaction between nanoparticles and cells has been studied extensively, but most research has focused on the effect of various nanoparticle characteristics, such as size, morphology, and surface charge, on the cellular uptake of nanoparticles. In contrast, there have been very few studies to assess the influence of cellular factors, such as growth factor responses, on the cellular uptake efficiency of nanoparticles. The aim of this study was to clarify the effects of epidermal growth factor (EGF) on the uptake efficiency of polystyrene nanoparticles (PS NPs) by A431 cells, a human carcinoma epithelial cell line. The results showed that EGF enhanced the uptake efficiency of A431 cells for PS NPs. In addition, inhibition and localization studies of PS NPs and EGF receptors (EGFRs) indicated that cellular uptake of PS NPs is related to the binding of EGF–EGFR complex and PS NPs. Different pathways are used to enter the cells depending on the presence or absence of EGF. In the presence of EGF, cellular uptake of PS NPs is via clathrin-mediated endocytosis, whereas, in the absence of EGF, uptake of PS NPs does not involve clathrin-mediated endocytosis. Our findings indicate that EGF enhances cellular uptake of PS NPs by clathrin-mediated endocytosis. This result could be important for developing safe nanoparticles and their safe use in medical applications. PMID:28629179

Epidermal Growth Factor Enhances Cellular Uptake of Polystyrene Nanoparticles by Clathrin-Mediated Endocytosis.

PubMed

Phuc, Le Thi Minh; Taniguchi, Akiyoshi

2017-06-19

The interaction between nanoparticles and cells has been studied extensively, but most research has focused on the effect of various nanoparticle characteristics, such as size, morphology, and surface charge, on the cellular uptake of nanoparticles. In contrast, there have been very few studies to assess the influence of cellular factors, such as growth factor responses, on the cellular uptake efficiency of nanoparticles. The aim of this study was to clarify the effects of epidermal growth factor (EGF) on the uptake efficiency of polystyrene nanoparticles (PS NPs) by A431 cells, a human carcinoma epithelial cell line. The results showed that EGF enhanced the uptake efficiency of A431 cells for PS NPs. In addition, inhibition and localization studies of PS NPs and EGF receptors (EGFRs) indicated that cellular uptake of PS NPs is related to the binding of EGF-EGFR complex and PS NPs. Different pathways are used to enter the cells depending on the presence or absence of EGF. In the presence of EGF, cellular uptake of PS NPs is via clathrin-mediated endocytosis, whereas, in the absence of EGF, uptake of PS NPs does not involve clathrin-mediated endocytosis. Our findings indicate that EGF enhances cellular uptake of PS NPs by clathrin-mediated endocytosis. This result could be important for developing safe nanoparticles and their safe use in medical applications.

Q fever in pregnant goats: humoral and cellular immune responses

PubMed Central

2013-01-01

Q fever is a zoonosis caused by the intracellular bacterium Coxiella burnetii. Both humoral and cellular immunity are important in the host defence against intracellular bacteria. Little is known about the immune response to C. burnetii infections in domestic ruminants even though these species are the major source of Q fever in humans. To investigate the goat’s immune response we inoculated groups of pregnant goats via inhalation with a Dutch outbreak isolate of C. burnetii. All animals were successfully infected. Phase 1 and Phase 2 IgM- and IgG-specific antibodies were measured. Cellular immune responses were investigated by interferon-gamma, enzyme-linked immunosorbent spot test (IFN-γ Elispot), lymphocyte proliferation test (LPT) and systemic cytokines. After two weeks post inoculation (wpi), a strong anti-C. burnetii Phase 2 IgM and IgG antibody response was observed while the increase in IgM anti-Phase 1 antibodies was less pronounced. IgG anti-Phase 1 antibodies started to rise at 6 wpi. Cellular immune responses were observed after parturition. Our results demonstrated humoral and cellular immune responses to C. burnetii infection in pregnant goats. Cell-mediated immune responses did not differ enough to distinguish between Coxiella-infected and non-infected pregnant animals, whereas a strong-phase specific antibody response is detected after 2 wpi. This humoral immune response may be useful in the early detection of C. burnetii-infected pregnant goats. PMID:23915213

Cognitive effects of radiation emitted by cellular phones: the influence of exposure side and time.

PubMed

Luria, Roy; Eliyahu, Ilan; Hareuveny, Ronen; Margaliot, Menachem; Meiran, Nachshon

2009-04-01

This study examined the time dependence effects of exposure to radiofrequency radiation (RFR) emitted by standard GSM cellular phones on the cognitive functions of humans. A total of 48 healthy right-handed male subjects performed a spatial working memory task (that required either a left-hand or a right-hand response) while being exposed to one of two GSM phones placed at both sides of the head. The subjects were randomly divided into three groups. Each group was exposed to one of three exposure conditions: left-side of the head, right-side, or sham-exposure. The experiment consisted of 12 blocks of trials. Response times (RTs) and accuracy of the responses were recorded. It was found that the average RT of the right-hand responses under left-side exposure condition was significantly longer than those of the right-side and sham-exposure groups averaged together during the first two time blocks. These results confirmed the existence of an effect of exposure on RT, as well as the fact that exposure duration (together with the responding hand and the side of exposure) may play an important role in producing detectable RFR effects on performance. Differences in these parameters might be the reason for the failure of certain studies to detect or replicate RFR effects. (c) 2008 Wiley-Liss, Inc.

Improved Endpoints for Cancer Immunotherapy Trials

PubMed Central

Eggermont, Alexander M. M.; Janetzki, Sylvia; Hodi, F. Stephen; Ibrahim, Ramy; Anderson, Aparna; Humphrey, Rachel; Blumenstein, Brent; Wolchok, Jedd

2010-01-01

Unlike chemotherapy, which acts directly on the tumor, cancer immunotherapies exert their effects on the immune system and demonstrate new kinetics that involve building a cellular immune response, followed by changes in tumor burden or patient survival. Thus, adequate design and evaluation of some immunotherapy clinical trials require a new development paradigm that includes reconsideration of established endpoints. Between 2004 and 2009, several initiatives facilitated by the Cancer Immunotherapy Consortium of the Cancer Research Institute and partner organizations systematically evaluated an immunotherapy-focused clinical development paradigm and created the principles for redefining trial endpoints. On this basis, a body of clinical and laboratory data was generated that supports three novel endpoint recommendations. First, cellular immune response assays generate highly variable results. Assay harmonization in multicenter trials may minimize variability and help to establish cellular immune response as a reproducible biomarker, thus allowing investigation of its relationship with clinical outcomes. Second, immunotherapy may induce novel patterns of antitumor response not captured by Response Evaluation Criteria in Solid Tumors or World Health Organization criteria. New immune-related response criteria were defined to more comprehensively capture all response patterns. Third, delayed separation of Kaplan–Meier curves in randomized immunotherapy trials can affect results. Altered statistical models describing hazard ratios as a function of time and recognizing differences before and after separation of curves may allow improved planning of phase III trials. These recommendations may improve our tools for cancer immunotherapy trials and may offer a more realistic and useful model for clinical investigation. PMID:20826737

The nociception genes painless and Piezo are required for the cellular immune response of Drosophila larvae to wasp parasitization.

PubMed

Tokusumi, Yumiko; Tokusumi, Tsuyoshi; Schulz, Robert A

2017-05-13

In vertebrates, interaction between the nervous system and immune system is important to protect a challenged host from stress inputs from external sources. In this study, we demonstrate that sensory neurons are involved in the cellular immune response elicited by wasp infestation of Drosophila larvae. Multidendritic class IV neurons sense contacts from external stimuli and induce avoidance behaviors for host defense. Our findings show that inactivation of these sensory neurons impairs the cellular response against wasp parasitization. We also demonstrate that the nociception genes encoding the mechanosensory receptors Painless and Piezo, both expressed in class IV neurons, are essential for the normal cellular immune response to parasite challenge. Copyright © 2017. Published by Elsevier Inc.

Endoplasmic Reticulum and the Unfolded Protein Response: Dynamics and Metabolic Integration

PubMed Central

Bravo, Roberto; Parra, Valentina; Gatica, Damián; Rodriguez, Andrea E.; Torrealba, Natalia; Paredes, Felipe; Wang, Zhao V.; Zorzano, Antonio; Hill, Joseph A.; Jaimovich, Enrique; Quest, Andrew F.G.; Lavandero, Sergio

2013-01-01

The endoplasmic reticulum (ER) is a dynamic intracellular organelle with multiple functions essential for cellular homeostasis, development, and stress responsiveness. In response to cellular stress, a well-established signaling cascade, the unfolded protein response (UPR), is activated. This intricate mechanism is an important means of reestablishing cellular homeostasis and alleviating the inciting stress. Now, emerging evidence has demonstrated that the UPR influences cellular metabolism through diverse mechanisms, including calcium and lipid transfer, raising the prospect of involvement of these processes in the pathogenesis of disease, including neurodegeneration, cancer, diabetes mellitus and cardiovascular disease. Here, we review the distinct functions of the ER and UPR from a metabolic point of view, highlighting their association with prevalent pathologies. PMID:23317820

The response of a boreal deep-sea sponge holobiont to acute thermal stress.

PubMed

Strand, R; Whalan, S; Webster, N S; Kutti, T; Fang, J K H; Luter, H M; Bannister, R J

2017-05-22

Effects of elevated seawater temperatures on deep-water benthos has been poorly studied, despite reports of increased seawater temperature (up to 4 °C over 24 hrs) coinciding with mass mortality events of the sponge Geodia barretti at Tisler Reef, Norway. While the mechanisms driving these mortality events are unclear, manipulative laboratory experiments were conducted to quantify the effects of elevated temperature (up to 5 °C, above ambient levels) on the ecophysiology (respiration rate, nutrient uptake, cellular integrity and sponge microbiome) of G. barretti. No visible signs of stress (tissue necrosis or discolouration) were evident across experimental treatments; however, significant interactive effects of time and treatment on respiration, nutrient production and cellular stress were detected. Respiration rates and nitrogen effluxes doubled in responses to elevated temperatures (11 °C & 12 °C) compared to control temperatures (7 °C). Cellular stress, as measured through lysosomal destabilisation, was 2-5 times higher at elevated temperatures than for control temperatures. However, the microbiome of G. barretti remained stable throughout the experiment, irrespective of temperature treatment. Mortality was not evident and respiration rates returned to pre-experimental levels during recovery. These results suggest other environmental processes, either alone or in combination with elevated temperature, contributed to the mortality of G. barretti at Tisler reef.

Curcumin in combined cancer therapy.

PubMed

Troselj, Koraljka Gall; Kujundzic, Renata Novak

2014-01-01

The mechanisms of beneficial preventive and therapeutic effects achieved by traditional and complementary medicine are currently being deciphered in molecular medicine. Curcumin, a yellow-colored polyphenol derived from the rhizome of turmeric (Curcuma longa), influences a wide variety of cellular processes through the reshaping of many molecular targets. One of them, nuclear factor kappa B (NF-κB), represents a strong mediator of inflammation and, in a majority of systems, supports the pro-proliferative features of cancer cells. The application of various anticancer drugs, cytostatics, triggers signals which lead to an increase in cellular NF-κB activity. As a consequence, cancer cells often reshape their survival signaling pathways and, over time, become resistant to applied therapy. Curcumin was shown to be a strong inhibitor of NF-κB activity and its inhibitory effect on NF-κB related pathways often leads to cellular apoptotic response. All these facts, tested and confirmed in many different biological systems, have paved the way for research aimed to elucidate the potential beneficial effects of combining curcumin and various anti-cancer drugs in order to establish more efficient and less toxic cancer treatment modalities. This review addresses certain aspects of NF-κB-related inflammatory response, its role in carcinogenesis and therapy benefits that may be gained through silencing NF-κB by selectively combining curcumin and various anticancer drugs.

From receptor binding kinetics to signal transduction; a missing link in predicting in vivo drug-action.

PubMed

Nederpelt, Indira; Kuzikov, Maria; de Witte, Wilbert E A; Schnider, Patrick; Tuijt, Bruno; Gul, Sheraz; IJzerman, Adriaan P; de Lange, Elizabeth C M; Heitman, Laura H

2017-10-26

An important question in drug discovery is how to overcome the significant challenge of high drug attrition rates due to lack of efficacy and safety. A missing link in the understanding of determinants for drug efficacy is the relation between drug-target binding kinetics and signal transduction, particularly in the physiological context of (multiple) endogenous ligands. We hypothesized that the kinetic binding parameters of both drug and endogenous ligand play a crucial role in determining cellular responses, using the NK1 receptor as a model system. We demonstrated that the binding kinetics of both antagonists (DFA and aprepitant) and endogenous agonists (NKA and SP) have significantly different effects on signal transduction profiles, i.e. potency values, in vitro efficacy values and onset rate of signal transduction. The antagonistic effects were most efficacious with slowly dissociating aprepitant and slowly associating NKA while the combination of rapidly dissociating DFA and rapidly associating SP had less significant effects on the signal transduction profiles. These results were consistent throughout different kinetic assays and cellular backgrounds. We conclude that knowledge of the relationship between in vitro drug-target binding kinetics and cellular responses is important to ultimately improve the understanding of drug efficacy in vivo.

Characterizing heterogeneous cellular responses to perturbations.

PubMed

Slack, Michael D; Martinez, Elisabeth D; Wu, Lani F; Altschuler, Steven J

2008-12-09

Cellular populations have been widely observed to respond heterogeneously to perturbation. However, interpreting the observed heterogeneity is an extremely challenging problem because of the complexity of possible cellular phenotypes, the large dimension of potential perturbations, and the lack of methods for separating meaningful biological information from noise. Here, we develop an image-based approach to characterize cellular phenotypes based on patterns of signaling marker colocalization. Heterogeneous cellular populations are characterized as mixtures of phenotypically distinct subpopulations, and responses to perturbations are summarized succinctly as probabilistic redistributions of these mixtures. We apply our method to characterize the heterogeneous responses of cancer cells to a panel of drugs. We find that cells treated with drugs of (dis-)similar mechanism exhibit (dis-)similar patterns of heterogeneity. Despite the observed phenotypic diversity of cells observed within our data, low-complexity models of heterogeneity were sufficient to distinguish most classes of drug mechanism. Our approach offers a computational framework for assessing the complexity of cellular heterogeneity, investigating the degree to which perturbations induce redistributions of a limited, but nontrivial, repertoire of underlying states and revealing functional significance contained within distinct patterns of heterogeneous responses.

Modulation of Immune Response by Organophosphorus Pesticides: Fishes as a Potential Model in Immunotoxicology

PubMed Central

Díaz-Resendiz, K. J. G.; Toledo-Ibarra, G. A.; Girón-Pérez, M. I.

2015-01-01

Immune response is modulated by different substances that are present in the environment. Nevertheless, some of these may cause an immunotoxic effect. In this paper, the effect of organophosphorus pesticides (frequent substances spilled in aquatic ecosystems) on the immune system of fishes and in immunotoxicology is reviewed. Furthermore, some cellular and molecular mechanisms that might be involved in immunoregulation mechanisms of organophosphorus pesticides are discussed. PMID:25973431

Analysis of cellular responses of macrophages to zinc ions and zinc oxide nanoparticles: a combined targeted and proteomic approach.

PubMed

Triboulet, Sarah; Aude-Garcia, Catherine; Armand, Lucie; Gerdil, Adèle; Diemer, Hélène; Proamer, Fabienne; Collin-Faure, Véronique; Habert, Aurélie; Strub, Jean-Marc; Hanau, Daniel; Herlin, Nathalie; Carrière, Marie; Van Dorsselaer, Alain; Rabilloud, Thierry

2014-06-07

Two different zinc oxide nanoparticles, as well as zinc ions, are used to study the cellular responses of the RAW 264 macrophage cell line. A proteomic screen is used to provide a wide view of the molecular effects of zinc, and the most prominent results are cross-validated by targeted studies. Furthermore, the alteration of important macrophage functions (e.g. phagocytosis) by zinc is also investigated. The intracellular dissolution/uptake of zinc is also studied to further characterize zinc toxicity. Zinc oxide nanoparticles dissolve readily in the cells, leading to high intracellular zinc concentrations, mostly as protein-bound zinc. The proteomic screen reveals a rather weak response in the oxidative stress response pathway, but a strong response both in the central metabolism and in the proteasomal protein degradation pathway. Targeted experiments confirm that carbohydrate catabolism and proteasome are critical determinants of sensitivity to zinc, which also induces DNA damage. Conversely, glutathione levels and phagocytosis appear unaffected at moderately toxic zinc concentrations.

Proteome response of fish under multiple stress exposure: Effects of pesticide mixtures and temperature increase.

PubMed

Gandar, Allison; Laffaille, Pascal; Marty-Gasset, Nathalie; Viala, Didier; Molette, Caroline; Jean, Séverine

2017-03-01

Aquatic systems can be subjected to multiple stressors, including pollutant cocktails and elevated temperature. Evaluating the combined effects of these stressors on organisms is a great challenge in environmental sciences. To the best of our knowledge, this is the first study to assess the molecular stress response of an aquatic fish species subjected to individual and combined pesticide mixtures and increased temperatures. For that, goldfish (Carassius auratus) were acclimated to two different temperatures (22 and 32°C) for 15 days. They were then exposed for 96h to a cocktail of herbicides and fungicides (S-metolachlor, isoproturon, linuron, atrazine-desethyl, aclonifen, pendimethalin and tebuconazole) at two environmentally relevant concentrations (total concentrations of 8.4μgL -1 and 42μgL -1 ) at these two temperatures (22 and 32°C). The molecular response in liver was assessed by 2D-proteomics. Identified proteins were integrated using pathway enrichment analysis software to determine the biological functions involved in the individual or combined stress responses and to predict the potential deleterious outcomes. The pesticide mixtures elicited pathways involved in cellular stress response, carbohydrate, protein and lipid metabolisms, methionine cycle, cellular functions, cell structure and death control, with concentration- and temperature-dependent profiles of response. We found that combined temperature increase and pesticide exposure affected the cellular stress response: the effects of oxidative stress were more marked and there was a deregulation of the cell cycle via apoptosis inhibition. Moreover a decrease in the formation of glucose by liver and in ketogenic activity was observed in this multi-stress condition. The decrease in both pathways could reflect a shift from a metabolic compensation strategy to a conservation state. Taken together, our results showed (1) that environmental cocktails of herbicides and fungicides induced important changes in pathways involved in metabolism, cell structure and cell cycle, with possible deleterious outcomes at higher biological scales and (2) that increasing temperature could affect the response of fish to pesticide exposure. Copyright © 2017 Elsevier B.V. All rights reserved.

Evaluation of Toxic Effects of Aeration and Trichloroethylene Oxidation on Methanotrophic Bacteria Grown with Different Nitrogen Sources

PubMed Central

Chu, Kung-Hui; Alvarez-Cohen, Lisa

1999-01-01

In this study we evaluated specific and nonspecific toxic effects of aeration and trichloroethylene (TCE) oxidation on methanotrophic bacteria grown with different nitrogen sources (nitrate, ammonia, and molecular nitrogen). The specific toxic effects, exerted directly on soluble methane monooxygenase (sMMO), were evaluated by comparing changes in methane uptake rates and naphthalene oxidation rates following aeration and/or TCE oxidation. Nonspecific toxic effects, defined as general cellular damage, were examined by using a combination of epifluorescent cellular stains to measure viable cell numbers based on respiratory activity and measuring formate oxidation activities following aeration and TCE transformation. Our results suggest that aeration damages predominantly sMMO rather than other general cellular components, whereas TCE oxidation exerts a broad range of toxic effects that damage both specific and nonspecific cellular functions. TCE oxidation caused sMMO-catalyzed activity and respiratory activity to decrease linearly with the amount of substrate degraded. Severe TCE oxidation toxicity resulted in total cessation of the methane, naphthalene, and formate oxidation activities and a 95% decrease in the respiratory activity of methanotrophs. The failure of cells to recover even after 7 days of incubation with methane suggests that cellular recovery following severe TCE product toxicity is not always possible. Our evidence suggests that generation of greater amounts of sMMO per cell due to nitrogen fixation may be responsible for enhanced TCE oxidation activities of nitrogen-fixing methanotrophs rather than enzymatic protection mechanisms associated with the nitrogenase enzymes. PMID:9925614

Cell Phone and Face-to-Face Interview Responses in Population-Based Surveys: How Do They Compare?

ERIC Educational Resources Information Center

Mahfoud, Ziyad; Ghandour, Lilian; Ghandour, Blanche; Mokdad, Ali H.; Sibai, Abla M.

2015-01-01

Findings on the reliability and cost-effectiveness of the use of cellular phones vis-à-vis face-to-face interviews in investigating health behaviors and conditions are presented for a national epidemiological sample from Lebanon. Using self-reported responses on identical questions, percentage agreement, ? statistics, and McNemar's test were used…

Investigating Oxidative Stress and Inflammatory Responses Elicited by Silver Nanoparticles Using High-Throughput Reporter Genes in HepG2 Cells: Effect of Size, Surface Coating, and Intracellular Uptake

EPA Science Inventory

Abstract Silver nanoparticles (Ag NP) have been shown to generate reactive oxygen species; however, the association between physicochemical characteristics of nanoparticles and cellular stress responses elicited by exposure has not been elucidated. Here, we examined three key...

Stress biology and aging mechanisms: toward understanding the deep connection between adaptation to stress and longevity.

PubMed

Epel, Elissa S; Lithgow, Gordon J

2014-06-01

The rate of biological aging is modulated in part by genes interacting with stressor exposures. Basic research has shown that exposure to short-term stress can strengthen cellular responses to stress ("hormetic stress"). Hormetic stress promotes longevity in part through enhanced activity of molecular chaperones and other defense mechanisms. In contrast, prolonged exposure to stress can overwhelm compensatory responses ("toxic stress") and shorten lifespan. One key question is whether the stressors that are well understood in basic models of aging can help us understand psychological stressors and human health. The psychological stress response promotes regulatory changes important in aging (e.g., increases in stress hormones, inflammation, oxidative stress, insulin). The negative effects of severe stress are well documented in humans. Potential positive effects of acute stress (stress resistance) are less studied, especially at the cellular level. Can stress resistance slow the rate of aging in humans, as it does in model organisms? If so, how can we promote stress resistance in humans? We urge a new research agenda embracing the continuum from cellular stress to psychological stress, using basic and human research in tandem. This will require interdisciplinary novel approaches that hold much promise for understanding and intervening in human chronic disease. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Nucleolus-derived mediators in oncogenic stress response and activation of p53-dependent pathways.

PubMed

Stępiński, Dariusz

2016-08-01

Rapid growth and division of cells, including tumor ones, is correlated with intensive protein biosynthesis. The output of nucleoli, organelles where translational machineries are formed, depends on a rate of particular stages of ribosome production and on accessibility of elements crucial for their effective functioning, including substrates, enzymes as well as energy resources. Different factors that induce cellular stress also often lead to nucleolar dysfunction which results in ribosome biogenesis impairment. Such nucleolar disorders, called nucleolar or ribosomal stress, usually affect cellular functioning which in fact is a result of p53-dependent pathway activation, elicited as a response to stress. These pathways direct cells to new destinations such as cell cycle arrest, damage repair, differentiation, autophagy, programmed cell death or aging. In the case of impaired nucleolar functioning, nucleolar and ribosomal proteins mediate activation of the p53 pathways. They are also triggered as a response to oncogenic factor overexpression to protect tissues and organs against extensive proliferation of abnormal cells. Intentional impairment of any step of ribosome biosynthesis which would direct the cells to these destinations could be a strategy used in anticancer therapy. This review presents current knowledge on a nucleolus, mainly in relation to cancer biology, which is an important and extremely sensitive element of the mechanism participating in cellular stress reaction mediating activation of the p53 pathways in order to counteract stress effects, especially cancer development.

Cellular stress induced by resazurin leads to autophagy and cell death via production of reactive oxygen species and mitochondrial impairment.

PubMed

Erikstein, Bjarte S; Hagland, Hanne R; Nikolaisen, Julie; Kulawiec, Mariola; Singh, Keshav K; Gjertsen, Bjørn T; Tronstad, Karl J

2010-10-15

Mitochondrial bioenergetics and reactive oxygen species (ROS) often play important roles in cellular stress mechanisms. In this study we investigated how these factors are involved in the stress response triggered by resazurin (Alamar Blue) in cultured cancer cells. Resazurin is a redox reactive compound widely used as reporter agent in assays of cell biology (e.g. cell viability and metabolic activity) due to its colorimetric and fluorimetric properties. In order to investigate resazurin-induced stress mechanisms we employed cells affording different metabolic and regulatory phenotypes. In HL-60 and Jurkat leukemia cells resazurin caused mitochondrial disintegration, respiratory dysfunction, reduced proliferation, and cell death. These effects were preceded by a burst of ROS, especially in HL-60 cells which were also more sensitive and contained autophagic vesicles. Studies in Rho(0) cells (devoid of mitochondrial DNA) indicated that the stress response does not depend on the rates of mitochondrial respiration. The anti-proliferative effect of resazurin was confirmed in native acute myelogenous leukemia (AML) blasts. In conclusion, the data suggest that resazurin triggers cellular ROS production and thereby initiates a stress response leading to mitochondrial dysfunction, reduced proliferation, autophagy, and cell degradation. The ability of cells to tolerate this type of stress may be important in toxicity and chemoresistance. © 2010 Wiley-Liss, Inc.

Investigating the Cellular and Metabolic Responses of World-Class Canoeists Training: A Sportomics Approach

PubMed Central

Coelho, Wagner Santos; Viveiros de Castro, Luis; Deane, Elizabeth; Magno-França, Alexandre; Bassini, Adriana; Cameron, Luiz-Claudio

2016-01-01

(1) Background: We have been using the Sportomics approach to evaluate biochemical and hematological changes in response to exercise. The aim of this study was to evaluate the metabolic and hematologic responses of world-class canoeists during a training session; (2) Methods: Blood samples were taken at different points and analyzed for their hematological properties, activities of selected enzymes, hormones, and metabolites; (3) Results: Muscle stress biomarkers were elevated in response to exercise which correlated with modifications in the profile of white blood cells, where a leukocyte rise was observed after the canoe session. These results were accompanied by an increase in other exercise intensity parameters such as lactatemia and ammonemia. Adrenocorticotropic hormone and cortisol increased during the exercise sessions. The acute rise in both erythrocytes and white blood profile were probably due to muscle cell damage, rather than hepatocyte integrity impairment; (4) Conclusion: The cellular and metabolic responses found here, together with effective nutrition support, are crucial to understanding the effects of exercise in order to assist in the creation of new training and recovery planning. Also we show that Sportomics is a primal tool for training management and performance improvement, as well as to the understanding of metabolic response to exercise. PMID:27845704

Cervical cancer cells (HeLa) response to photodynamic therapy using a zinc phthalocyanine photosensitizer.

PubMed

Hodgkinson, Natasha; Kruger, Cherie Ann; Mokwena, Mpho; Abrahamse, Heidi

2017-12-01

Cervical cancer is the most common gynecological malignancy worldwide, and the leading cause of cancer related deaths among females. Conventional treatment for early cervical cancer is radical hysterectomy. In locally advanced cancer the treatment of choice is concurrent chemo radiation. Although such treatment methods show promise, they do have adverse side effects. To minimize these effects, as well as prevent cancer re-occurrence, new treatment methods are being investigated. Photodynamic therapy (PDT) involves the selective uptake of a photosensitizer (PS) by cancer cells, illumination with light of an appropriate wavelength that triggers a photochemical reaction leading to the generation of reactive oxygen and subsequent tumor regression. The effect of PDT on a cervical cancer cell line (HeLa) was assessed by exposing cultured cells to a sulphonated zinc phthalocyanine PS (ZnPcS mix ) and irradiating the cells using a 673nm diode laser. The effects were measured using the Trypan blue viability assay, adenosine triphosphate assay (ATP) luminescence assay for proliferation, Lactate Dehydrogenase (LDH) membrane integrity cytotoxicity assay, and fluorescent microscopy to assess PS cellular localization and nuclear damage. Fluorescent microscopy revealed localization of the PS in the cytoplasm and perinuclear region of HeLa cells. PDT treated cellular responses showed dose dependent structural changes, with decreased cell viability and proliferation, as well as considerable membrane damage. Hoechst stained cells also revealed DNA damage in PDT treated cells. The final findings from this study suggest that ZnPcS mix is a promising PS for the PDT treatment of cervical cancer in vitro, where a significant 85% cellular cytotoxicity with only 25% cellular viability was noted in cells which received 1μM ZnPcS mix when an 8J/cm 2 fluence was applied. Copyright © 2017 Elsevier B.V. All rights reserved.

The Acute Effects of Leptin Require PI3K Signaling in the Hypothalamic Ventral Premammillary Nucleus

PubMed Central

Williams, Kevin W.; Sohn, Jong-Woo; Donato, Jose; Lee, Charlotte E.; Zhao, Jean J.; Elmquist, Joel K.; Elias, Carol F.

2012-01-01

Evidence suggests that the role played by the adipocyte-derived hormone leptin in female reproductive physiologyis mediated in part by neurons located within the ventral premammillary nucleus (PMV). Leptin activates PMV neurons; however, the intracellular signaling pathway and channel(s) involved remain undefined. Notably, leptin's excitatory and inhibitory effects within hypothalamic and brainstem nuclei share the intracellular signaling cascade phosphoinositide 3 kinase (PI3K). Therefore, we assessed whether PI3K signaling is required for the acute effect of leptin to alter cellular activity of PMV neurons that express leptin receptors (LepR PMV neurons). Leptin caused a rapid depolarization in the majority of LepR PMV neurons in patch-clamp recordings of hypothalamic slices, while a subset of LepR PMV neurons were hyperpolarized in response to leptin. Data were obtained from both male and female mice and results demonstrate that the acute effect of leptin on LepR PMV neurons was identical for both sexes. Pharmacological inhibition of PI3K prevented the acute leptin-induced change in neuronal activity of LepR PMV neurons, indicating a PI3K-dependent mechanism of leptin action. Similarly, mice with genetically disrupted PI3K signaling in LepR PMV neurons failed to alter cellular activity in response to leptin. Moreover, the leptin-induced depolarization was dependent on a putative TRPC channel. In contrast, the leptin-induced-hyperpolarization required the activation of a putative Katp channel. Collectively, these results suggest that PI3K signaling in LepR PMV neurons is essential for leptin-induced alteration in cellular activity, and these data may suggest a cellular correlate in which leptin contributes to the initiation of reproductive development. PMID:21917798

Humoral and Cellular Response in Humans After Immunization with Influenza Vaccine

PubMed Central

Ruben, Frederick L.; Jackson, George G.; Gotoff, Samuel P.

1973-01-01

The peripheral blood lymphocyte response and hemagglutination inhibition antibody titers were measured in nine adults before and after immunization with a killed split influenza virus vaccine. Cord blood lymphocytes were tested with the influenza antigen to exclude a nonspecific mitogenic effect. All of the subjects demonstrated preexisting antibody titers and antigen recognition by lymphocytes prior to immunization. The in vitro lymphocyte response after vaccination parallels the humoral antibody response to influenza antigen. PMID:4762112

Cord blood Streptococcus pneumoniae‐specific cellular immune responses predict early pneumococcal carriage in high‐risk infants in Papua New Guinea

PubMed Central

Francis, J. P.; Richmond, P. C.; Strickland, D.; Prescott, S. L.; Pomat, W. S.; Michael, A.; Nadal‐Sims, M. A.; Edwards‐Devitt, C. J.; Holt, P. G.; Lehmann, D.

2016-01-01

Summary In areas where Streptococcus pneumoniae is highly endemic, infants experience very early pneumococcal colonization of the upper respiratory tract, with carriage often persisting into adulthood. We aimed to explore whether newborns in high‐risk areas have pre‐existing pneumococcal‐specific cellular immune responses that may affect early pneumococcal acquisition. Cord blood mononuclear cells (CBMC) of 84 Papua New Guinean (PNG; high endemic) and 33 Australian (AUS; low endemic) newborns were stimulated in vitro with detoxified pneumolysin (dPly) or pneumococcal surface protein A (PspA; families 1 and 2) and compared for cytokine responses. Within the PNG cohort, associations between CBMC dPly and PspA‐induced responses and pneumococcal colonization within the first month of life were studied. Significantly higher PspA‐specific interferon (IFN)‐γ, tumour necrosis factor (TNF)‐α, interleukin (IL)‐5, IL‐6, IL‐10 and IL‐13 responses, and lower dPly‐IL‐6 responses were produced in CBMC cultures of PNG compared to AUS newborns. Higher CBMC PspA‐IL‐5 and PspA‐IL‐13 responses correlated with a higher proportion of cord CD4 T cells, and higher dPly‐IL‐6 responses with a higher frequency of cord antigen‐presenting cells. In the PNG cohort, higher PspA‐specific IL‐5 and IL‐6 CBMC responses were associated independently and significantly with increased risk of earlier pneumococcal colonization, while a significant protective effect was found for higher PspA‐IL‐10 CBMC responses. Pneumococcus‐specific cellular immune responses differ between children born in pneumococcal high versus low endemic settings, which may contribute to the higher risk of infants in high endemic settings for early pneumococcal colonization, and hence disease. PMID:27859014

High content cell-based assay for the inflammatory pathway

NASA Astrophysics Data System (ADS)

Mukherjee, Abhishek; Song, Joon Myong

2015-07-01

Cellular inflammation is a non-specific immune response to tissue injury that takes place via cytokine network orchestration to maintain normal tissue homeostasis. However chronic inflammation that lasts for a longer period, plays the key role in human diseases like neurodegenerative disorders and cancer development. Understanding the cellular and molecular mechanisms underlying the inflammatory pathways may be effective in targeting and modulating their outcome. Tumor necrosis factor alpha (TNF-α) is a pro-inflammatory cytokine that effectively combines the pro-inflammatory features with the pro-apoptotic potential. Increased levels of TNF-α observed during acute and chronic inflammatory conditions are believed to induce adverse phenotypes like glucose intolerance and abnormal lipid profile. Natural products e. g., amygdalin, cinnamic acid, jasmonic acid and aspirin have proven efficacy in minimizing the TNF-α induced inflammation in vitro and in vivo. Cell lysis-free quantum dot (QDot) imaging is an emerging technique to identify the cellular mediators of a signaling cascade with a single assay in one run. In comparison to organic fluorophores, the inorganic QDots are bright, resistant to photobleaching and possess tunable optical properties that make them suitable for long term and multicolor imaging of various components in a cellular crosstalk. Hence we tested some components of the mitogen activated protein kinase (MAPK) pathway during TNF-α induced inflammation and the effects of aspirin in HepG2 cells by QDot multicolor imaging technique. Results demonstrated that aspirin showed significant protective effects against TNF-α induced cellular inflammation. The developed cell based assay paves the platform for the analysis of cellular components in a smooth and reliable way.

Parasitoid wasp venom SERCA regulates Drosophila calcium levels and inhibits cellular immunity.

PubMed

Mortimer, Nathan T; Goecks, Jeremy; Kacsoh, Balint Z; Mobley, James A; Bowersock, Gregory J; Taylor, James; Schlenke, Todd A

2013-06-04

Because parasite virulence factors target host immune responses, identification and functional characterization of these factors can provide insight into poorly understood host immune mechanisms. The fruit fly Drosophila melanogaster is a model system for understanding humoral innate immunity, but Drosophila cellular innate immune responses remain incompletely characterized. Fruit flies are regularly infected by parasitoid wasps in nature and, following infection, flies mount a cellular immune response culminating in the cellular encapsulation of the wasp egg. The mechanistic basis of this response is largely unknown, but wasps use a mixture of virulence proteins derived from the venom gland to suppress cellular encapsulation. To gain insight into the mechanisms underlying wasp virulence and fly cellular immunity, we used a joint transcriptomic/proteomic approach to identify venom genes from Ganaspis sp.1 (G1), a previously uncharacterized Drosophila parasitoid species, and found that G1 venom contains a highly abundant sarco/endoplasmic reticulum calcium ATPase (SERCA) pump. Accordingly, we found that fly immune cells termed plasmatocytes normally undergo a cytoplasmic calcium burst following infection, and that this calcium burst is required for activation of the cellular immune response. We further found that the plasmatocyte calcium burst is suppressed by G1 venom in a SERCA-dependent manner, leading to the failure of plasmatocytes to become activated and migrate toward G1 eggs. Finally, by genetically manipulating plasmatocyte calcium levels, we were able to alter fly immune success against G1 and other parasitoid species. Our characterization of parasitoid wasp venom proteins led us to identify plasmatocyte cytoplasmic calcium bursts as an important aspect of fly cellular immunity.

Jahn-Teller effect in molecular electronics: quantum cellular automata

NASA Astrophysics Data System (ADS)

Tsukerblat, B.; Palii, A.; Clemente-Juan, J. M.; Coronado, E.

2017-05-01

The article summarizes the main results of application of the theory of the Jahn-Teller (JT) and pseudo JT effects to the description of molecular quantum dot cellular automata (QCA), a new paradigm of quantum computing. The following issues are discussed: 1) QCA as a new paradigm of quantum computing, principles and advantages; 2) molecular implementation of QCA; 3) role of the JT effect in charge trapping, encoding of binary information in the quantum cell and non-linear cell-cell response; 4) spin-switching in molecular QCA based on mixed-valence cell; 5) intervalence optical absorption in tetrameric molecular mixed-valence cell through the symmetry assisted approach to the multimode/multilevel JT and pseudo JT problems.

First cellular approach of the effects of global warming on groundwater organisms: a study of the HSP70 gene expression.

PubMed

Colson-Proch, Céline; Morales, Anne; Hervant, Frédéric; Konecny, Lara; Moulin, Colette; Douady, Christophe J

2010-05-01

Whereas the consequences of global warming at population or community levels are well documented, studies at the cellular level are still scarce. The study of the physiological or metabolic effects of such small increases in temperature (between +2 degrees C and +6 degrees C) is difficult because they are below the amplitude of the daily or seasonal thermal variations occurring in most environments. In contrast, subterranean biotopes are highly thermally buffered (+/-1 degrees C within a year), and underground water organisms could thus be particularly well suited to characterise cellular responses of global warming. To this purpose, we studied genes encoding chaperone proteins of the HSP70 family in amphipod crustaceans belonging to the ubiquitous subterranean genus Niphargus. An HSP70 sequence was identified in eight populations of two complexes of species of the Niphargus genus (Niphargus rhenorhodanensis and Niphargus virei complexes). Expression profiles were determined for one of these by reverse transcription and quantitative polymerase chain reaction, confirming the inducible nature of this gene. An increase in temperature of 2 degrees C seemed to be without effect on N. rhenorhodanensis physiology, whereas a heat shock of +6 degrees C represented an important thermal stress for these individuals. Thus, this study shows that although Niphargus individuals do not undergo any daily or seasonal thermal variations in underground water, they display an inducible HSP70 heat shock response. This controlled laboratory-based physiological experiment constitutes a first step towards field investigations of the cellular consequences of global warming on subterranean organisms.

Osteoporosis and alzheimer pathology: Role of cellular stress response and hormetic redox signaling in aging and bone remodeling

PubMed Central

Cornelius, Carolin; Koverech, Guido; Crupi, Rosalia; Di Paola, Rosanna; Koverech, Angela; Lodato, Francesca; Scuto, Maria; Salinaro, Angela T.; Cuzzocrea, Salvatore; Calabrese, Edward J.; Calabrese, Vittorio

2014-01-01

Alzheimer’s disease (AD) and osteoporosis are multifactorial progressive degenerative disorders. Increasing evidence shows that osteoporosis and hip fracture are common complication observed in AD patients, although the mechanisms underlying this association remain poorly understood. Reactive oxygen species (ROS) are emerging as intracellular redox signaling molecules involved in the regulation of bone metabolism, including receptor activator of nuclear factor-κB ligand-dependent osteoclast differentiation, but they also have cytotoxic effects that include lipoperoxidation and oxidative damage to proteins and DNA. ROS generation, which is implicated in the regulation of cellular stress response mechanisms, is an integrated, highly regulated, process under control of redox sensitive genes coding for redox proteins called vitagenes. Vitagenes, encoding for proteins such as heat shock proteins (Hsps) Hsp32, Hsp70, the thioredoxin, and the sirtuin protein, represent a systems controlling a complex network of intracellular signaling pathways relevant to life span and involved in the preservation of cellular homeostasis under stress conditions. Consistently, nutritional anti-oxidants have demonstrated their neuroprotective potential through a hormetic-dependent activation of vitagenes. The biological relevance of dose–response affects those strategies pointing to the optimal dosing to patients in the treatment of numerous diseases. Thus, the heat shock response has become an important hormetic target for novel cytoprotective strategies focusing on the pharmacological development of compounds capable of modulating stress response mechanisms. Here we discuss possible signaling mechanisms involved in the activation of vitagenes which, relevant to bone remodeling and through enhancement of cellular stress resistance provide a rationale to limit the deleterious consequences associated to homeostasis disruption with consequent impact on the aging process. PMID:24959146

Molecular Signaling Network Motifs Provide a Mechanistic Basis for Cellular Threshold Responses

PubMed Central

Bhattacharya, Sudin; Conolly, Rory B.; Clewell, Harvey J.; Kaminski, Norbert E.; Andersen, Melvin E.

2014-01-01

Background: Increasingly, there is a move toward using in vitro toxicity testing to assess human health risk due to chemical exposure. As with in vivo toxicity testing, an important question for in vitro results is whether there are thresholds for adverse cellular responses. Empirical evaluations may show consistency with thresholds, but the main evidence has to come from mechanistic considerations. Objectives: Cellular response behaviors depend on the molecular pathway and circuitry in the cell and the manner in which chemicals perturb these circuits. Understanding circuit structures that are inherently capable of resisting small perturbations and producing threshold responses is an important step towards mechanistically interpreting in vitro testing data. Methods: Here we have examined dose–response characteristics for several biochemical network motifs. These network motifs are basic building blocks of molecular circuits underpinning a variety of cellular functions, including adaptation, homeostasis, proliferation, differentiation, and apoptosis. For each motif, we present biological examples and models to illustrate how thresholds arise from specific network structures. Discussion and Conclusion: Integral feedback, feedforward, and transcritical bifurcation motifs can generate thresholds. Other motifs (e.g., proportional feedback and ultrasensitivity)produce responses where the slope in the low-dose region is small and stays close to the baseline. Feedforward control may lead to nonmonotonic or hormetic responses. We conclude that network motifs provide a basis for understanding thresholds for cellular responses. Computational pathway modeling of these motifs and their combinations occurring in molecular signaling networks will be a key element in new risk assessment approaches based on in vitro cellular assays. Citation: Zhang Q, Bhattacharya S, Conolly RB, Clewell HJ III, Kaminski NE, Andersen ME. 2014. Molecular signaling network motifs provide a mechanistic basis for cellular threshold responses. Environ Health Perspect 122:1261–1270; http://dx.doi.org/10.1289/ehp.1408244 PMID:25117432

ERE environment- and cell type-specific transcriptional effects of estrogen in normal endometrial cells.

PubMed

Lascombe, I; Sallot, M; Vuillermoz, C; Weisz, A; Adessi, G L; Jouvenot, M

1998-04-30

Our previous results have suggested a repression of E2 (17beta-estradiol) effect on the c-fos gene of cultured guinea-pig endometrial cells. To investigate this repression, the expression of three human c-fos gene recombinants, pFC1-BL (-2250/+41), pFC2-BL (-1400/+41) and pFC2E (-1300/-1050 and -230/+41), known to be E2-responsive in Hela cells, was studied in stromal (SC) and glandular epithelial cells (GEC). In both cellular types, pFC1-BL was not induced by E2, even in the presence of growth factors or co-transfected estrogen receptor. The pattern of pFC2-BL and pFC2E expression was strikingly different and depended on the cellular type: pFC2-BL and pFC2E induction was restricted to the glandular epithelial cells and did not occur in the SCs. We argue for a repression of E2 action which is dependent on the estrogen-responsive cis-acting element (ERE) environment and also cell type-specific involving DNA/protein and/or protein/protein interactions with cellular type-specific factors.

Adaptation response of Pseudomonas fragi on refrigerated solid matrix to a moderate electric field.

PubMed

Chen, Wenbo; Hu, Honghai; Zhang, Chunjiang; Huang, Feng; Zhang, Dequan; Zhang, Hong

2017-02-10

Moderate electric field (MEF) technology is a promising food preservation strategy since it relies on physical properties-rather than chemical additives-to preserve solid cellular foods during storage. However, the effectiveness of long-term MEF exposure on the psychrotrophic microorganisms responsible for the food spoilage at cool temperatures remains unclear. The spoilage-associated psychrotroph Pseudomonas fragi MC16 was obtained from pork samples stored at 7 °C. Continuous MEF treatment attenuated growth and resulted in subsequent adaptation of M16 cultured on nutrient agar plates at 7 °C, compared to the control cultures, as determined by biomass analysis and plating procedures. Moreover, intracellular dehydrogenase activity and ATP levels also indicated an initial effect of MEF treatment followed by cellular recovery, and extracellular β-galactosidase activity assays indicated no obvious changes in cell membrane permeability. Furthermore, microscopic observations using scanning and transmission electron microscopy revealed that MEF induced sublethal cellular injury during early treatment stages, but no notable changes in morphology or cytology on subsequent days. Our study provides direct evidence that psychrotrophic P. fragi MC16 cultured on nutrient agar plates at 7 °C are capable of adapting to MEF treatment.

New Therapeutic Concept of NAD Redox Balance for Cisplatin Nephrotoxicity

PubMed Central

Oh, Gi-Su; Kim, Hyung-Jin; Shen, AiHua; Lee, Su-Bin; Yang, Sei-Hoon; Shim, Hyeok; Cho, Eun-Young; Kwon, Kang-Beom; Kwak, Tae Hwan; So, Hong-Seob

2016-01-01

Cisplatin is a widely used chemotherapeutic agent for the treatment of various tumors. In addition to its antitumor activity, cisplatin affects normal cells and may induce adverse effects such as ototoxicity, nephrotoxicity, and peripheral neuropathy. Various mechanisms such as DNA adduct formation, mitochondrial dysfunction, oxidative stress, and inflammatory responses are closely associated with cisplatin-induced nephrotoxicity; however, the precise mechanism remains unclear. The cofactor nicotinamide adenine dinucleotide (NAD+) has emerged as a key regulator of cellular energy metabolism and homeostasis. Recent studies have demonstrated associations between disturbance in intracellular NAD+ levels and clinical progression of various diseases through the production of reactive oxygen species and inflammation. Furthermore, we demonstrated that reduction of the intracellular NAD+/NADH ratio is critically involved in cisplatin-induced kidney damage through inflammation and oxidative stress and that increase of the cellular NAD+/NADH ratio suppresses cisplatin-induced kidney damage by modulation of potential damage mediators such as oxidative stress and inflammatory responses. In this review, we describe the role of NAD+ metabolism in cisplatin-induced nephrotoxicity and discuss a potential strategy for the prevention or treatment of cisplatin-induced adverse effects with a particular focus on NAD+-dependent cellular pathways. PMID:26881219

Temporal metabolomic responses of cultured HepG2 liver cells to high fructose and high glucose exposures

USDA-ARS?s Scientific Manuscript database

High fructose consumption has been implicated with deleterious effects on human health, including hyperlipidemia elicited through de novo lipogenesis. However, more global effects of fructose on cellular metabolism have not been elucidated. In order to explore the metabolic impact of fructose-contai...

Cellular oxidative response from exposure to size-resolved ambient particulate matter

EPA Science Inventory

Recent studies suggest that particulate matter (PM) derived from different sources may differ in toxicity. The goal of this study was to characterize the in vitro effects of ambient PM and PM components from eight different locations in the U.S. and to investigate the effects of ...

Endogenous extra-cellular heat shock protein 72: releasing signal(s) and function.

PubMed

Fleshner, M; Johnson, J D

2005-08-01

Exposure to acute physical and/or psychological stressors induces a cascade of physiological changes collectively termed the stress response. The stress response is demonstrable at the behavioural, neural, endocrine and cellular levels. Stimulation of the stress response functions to improve an organism's chance of survival during acute stressor challenge. The current review focuses on one ubiquitous cellular stress response, up-regulation of heat shock protein 72 (Hsp72). Although a great deal is known about the function of intra-cellular Hsp72 during exposure to acute stressors, little is understood about the potential function of endogenous extra-cellular Hsp72 (eHsp72). The current review will develop the hypothesis that eHsp72 release may be a previously unrecognized feature of the acute stress response and may function as an endogenous 'danger signal' for the immune system. Specifically, it is proposed that exposure to physical or psychological acute stressors stimulate the release of endogenous eHsp72 into the blood via an alpha1-adrenergic receptor-mediated mechanism and that elevated eHsp72 functions to facilitate innate immunity in the presence of bacterial challenge.

Non linear processes modulated by low doses of radiation exposure

NASA Astrophysics Data System (ADS)

Mariotti, Luca; Ottolenghi, Andrea; Alloni, Daniele; Babini, Gabriele; Morini, Jacopo; Baiocco, Giorgio

The perturbation induced by radiation impinging on biological targets can stimulate the activation of several different pathways, spanning from the DNA damage processing to intra/extra -cellular signalling. In the mechanistic investigation of radiobiological damage this complex “system” response (e.g. omics, signalling networks, micro-environmental modifications, etc.) has to be taken into account, shifting from a focus on the DNA molecule solely to a systemic/collective view. An additional complication comes from the finding that the individual response of each of the involved processes is often not linear as a function of the dose. In this context, a systems biology approach to investigate the effects of low dose irradiations on intra/extra-cellular signalling will be presented, where low doses of radiation act as a mild perturbation of a robustly interconnected network. Results obtained through a multi-level investigation of both DNA damage repair processes (e.g. gamma-H2AX response) and of the activation kinetics for intra/extra cellular signalling pathways (e.g. NFkB activation) show that the overall cell response is dominated by non-linear processes - such as negative feedbacks - leading to possible non equilibrium steady states and to a poor signal-to-noise ratio. Together with experimental data of radiation perturbed pathways, different modelling approaches will be also discussed.

The detection of antigenic determinants of Acinetobacter baumannii.

PubMed

Tawfik, Dina M; Ahmad, Tarek A; Sheweita, Salah A; Haroun, Medhat; El-Sayed, Laila H

2017-06-01

Acinetobacter baumannii continues to pose a threat to burdened patients in ICUs all around the world. Lately, infection control techniques are not sufficient to curb A. baumannii's progression and chemotherapeutics are losing their potency against it. Thus, immunization became a key player in providing an ideal solution to the dilemma. None of the vaccines under investigation have reached the market and the search for a tailored vaccine remains a challenge. The notion of unravelling the bacterial antigens to design a novel epitope-based vaccine proved its merits. In this work, the propitious polysaccharide and protein antigenic determinants of A. baumannii were mapped by mimicking the infection. The immune response was evaluated by western blot, ELISA, and cellular proliferation assay techniques. The screening showed that OMPs induced the most eminent sustained IgG response. In addition, OMP gave the highest cellular proliferation and a fold increase in ELISA that reached up to 10-fold by week 6. Whilst, the LPS gave a rapid IgM response, that reached 5-fold and the response was visible from week 1 in the western blot. The OMPs had a more pronounced effect in eliciting a cellular immune response. The results elaborated the valuable role of using pure OMPs and detoxified LPS together; as a major cornerstone in designing an ideal vaccine against A. baumannii. Copyright © 2017 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

The fate of chemoresistance in triple negative breast cancer (TNBC)

PubMed Central

O’Reilly, Elma A.; Gubbins, Luke; Sharma, Shiva; Tully, Riona; Guang, Matthew Ho Zhing; Weiner-Gorzel, Karolina; McCaffrey, John; Harrison, Michele; Furlong, Fiona; Kell, Malcolm; McCann, Amanda

2015-01-01

Background Treatment options for women presenting with triple negative breast cancer (TNBC) are limited due to the lack of a therapeutic target and as a result, are managed with standard chemotherapy such as paclitaxel (Taxol®). Following chemotherapy, the ideal tumour response is apoptotic cell death. Post-chemotherapy, cells can maintain viability by undergoing viable cellular responses such as cellular senescence, generating secretomes which can directly enhance the malignant phenotype. Scope of Review How tumour cells retain viability in response to chemotherapeutic engagement is discussed. In addition we discuss the implications of this retained tumour cell viability in the context of the development of recurrent and metastatic TNBC disease. Current adjuvant and neo-adjuvant treatments available and the novel potential therapies that are being researched are also reviewed. Major conclusions Cellular senescence and cytoprotective autophagy are potential mechanisms of chemoresistance in TNBC. These two non-apoptotic outcomes in response to chemotherapy are inextricably linked and are neglected outcomes of investigation in the chemotherapeutic arena. Cellular fate assessments may therefore have the potential to predict TNBC patient outcome. General Significance Focusing on the fact that cancer cells can bypass the desired cellular apoptotic response to chemotherapy through cellular senescence and cytoprotective autophagy will highlight the importance of targeting non-apoptotic survival pathways to enhance chemotherapeutic efficacy. PMID:26676166

An introduction to the molecular basics of aryl hydrocarbon receptor biology.

PubMed

Abel, Josef; Haarmann-Stemmann, Thomas

2010-11-01

Depending on their chemical structure and properties, environmental chemicals and other xenobiotics that enter the cell can affect cellular function by either nonselective binding to cellular macromolecules or by interference with cellular receptors, which would initiate a more defined cell biological response. One of these intracellular chemosensor molecules is the aryl hydrocarbon receptor (AhR), a transcription factor of the bHLH/PAS family that is known to mediate the biochemical and toxic effects of dioxins, polyaromatic hydrocarbons and related compounds. Numerous investigations have revealed that the AhR is not only a master regulator of drug metabolism activated by anthropogenic chemicals, but is also triggered by natural and endogenous ligands and can influence cell biological endpoints such as growth and differentiation. Cutting-edge research has identified new intriguing functions of the AhR, such as during proteasomal degradation of steroid hormone receptors, the cellular UVB stress response and the differentiation of certain T-cell subsets. In this review we provide both a survey of the fundamental basics of AhR biology and an insight into new functional aspects of AhR signaling to further stimulate research on this intriguing transcription factor at the interface between toxicology, cell biology and immunology.

[Effects of several inhibitors of intracellular signaling on production of cytokines and signal proteins in RAW 264.7 cells cultivated with low dose ammonium].

PubMed

Novoselova, E G; Parfeniuk, S B; Glushkova, O V; Khrenov, M O; Novoselova, T V; Lunin, S M; Fesenko, E E

2012-01-01

Effects of four inhibitors of NF-kappaB, SAPK/JNK and TLR4 signaling, namely, inhibitor XII, SP600125, CLI-095 and Oxpapc on a macrophage response to low dose ammonium were studied in RAW 264.7 cells. Low dose ammonium induced pro-inflammatory response in cells as judged from enhanced production of TNF-alpha, IF-gamma, and IL-6, and by activation of signal cascades. The increase in production of cytokines, namely TNF, IFN, and IL-6, demonstrated that low-dose ammonium induced a pro-inflammatory cellular response. In addition, an activation of NF-kappaB and SAPK/JNK cascades, as well as enhancement of TLR4 expression was shown. Each of used inhibitors reduced to a variable degree the pro-inflammatory response of RAW 264.7 cells on chemical toxin by decreasing cytokine production. The inhibitor of NF-kappaB cascade, IKK Inhibitor XII, was more effective, and not only prevented the development of pro-inflammatory response induced by ammonium, but also decreased cytokine production below control values. The inhibitor of extra cellular domains of TLR2 and TLR4 (OxPAPC) had almost the same anti-inflammatory effect, and an addition of the inhibitor of JNK cascade (SP600125) to cell culture practically neutralized effect of ammonium ions by decreasing cytokine production to control level. Inhibitory analysis showed that activation of RAW 264.7 cells induced by chemical toxin coincide incompletely with intracellular signaling pathways that were early determined regarding macrophage's response to toxin from gram-negative bacteria. Nevertheless, application of the inhibitors defended RAW 264.7 from toxic effect of the low dose ammonium.

UV laser-ablated surface textures as potential regulator of cellular response.

PubMed

Chandra, Prafulla; Lai, Karen; Sung, Hak-Joon; Murthy, N Sanjeeva; Kohn, Joachim

2010-06-01

Textured surfaces obtained by UV laser ablation of poly(ethylene terephthalate) films were used to study the effect of shape and spacing of surface features on cellular response. Two distinct patterns, cones and ripples with spacing from 2 to 25 μm, were produced. Surface features with different shapes and spacings were produced by varying pulse repetition rate, laser fluence, and exposure time. The effects of the surface texture parameters, i.e., shape and spacing, on cell attachment, proliferation, and morphology of neonatal human dermal fibroblasts and mouse fibroblasts were studied. Cell attachment was the highest in the regions with cones at ∼4 μm spacing. As feature spacing increased, cell spreading decreased, and the fibroblasts became more circular, indicating a stress-mediated cell shrinkage. This study shows that UV laser ablation is a useful alternative to lithographic techniques to produce surface patterns for controlling cell attachment and growth on biomaterial surfaces.

Plasma generated in culture medium induces damages of HeLa cells due to flow phenomena

NASA Astrophysics Data System (ADS)

Sato, Yusuke; Sato, Takehiko; Yoshino, Daisuke

2018-03-01

Plasma in a liquid has been anticipated as an effective tool for medical applications, however, few reports have described cellular responses to plasma generated in a liquid similar to biological fluids. Herein we report the effects of plasma generated in a culture medium on HeLa cells. The plasma in the culture medium produced not only heat, shock waves, and reactive chemical species but also a jet flow with sub millimeter-sized bubbles. Cells exposed to the plasma exhibited detachment, morphological changes, and changes in the actin cytoskeletal structure. The experimental results suggest that wall shear stress over 160 Pa was generated on the surface of the cells by the plasma. It is one of the main factors that cause those cellular responses. We believe that our findings would provide valuable insight into advancements in medical applications of plasma in a liquid.

Cellular immune response experiment MA-031

NASA Technical Reports Server (NTRS)

Criswell, B. S.

1976-01-01

Significant changes in phytohemagglutinin (PHA) lymphocytic responsiveness occurred in the cellular immune response of three astronauts during the 9 day flight of the Apollo Soyuz Test Project. Parameters studied were white blood cell concentrations, lymphocyte numbers, B- and T-lymphocyte distributions in peripheral blood, and lymphocyte responsiveness to PHA, pokeweed mitogen, Concanavalin A, and influenza virus antigen.

Plant Nucleolar Stress Response, a New Face in the NAC-Dependent Cellular Stress Responses.

PubMed

Ohbayashi, Iwai; Sugiyama, Munetaka

2017-01-01

The nucleolus is the most prominent nuclear domain, where the core processes of ribosome biogenesis occur vigorously. All these processes are finely orchestrated by many nucleolar factors to build precisely ribosome particles. In animal cells, perturbations of ribosome biogenesis, mostly accompanied by structural disorders of the nucleolus, cause a kind of cellular stress to induce cell cycle arrest, senescence, or apoptosis, which is called nucleolar stress response. The best-characterized pathway of this stress response involves p53 and MDM2 as key players. p53 is a crucial transcription factor that functions in response to not only nucleolar stress but also other cellular stresses such as DNA damage stress. These cellular stresses release p53 from the inhibition by MDM2, an E3 ubiquitin ligase targeting p53, in various ways, which leads to p53-dependent activation of a set of genes. In plants, genetic impairments of ribosome biogenesis factors or ribosome components have been shown to cause characteristic phenotypes, including a narrow and pointed leaf shape, implying a common signaling pathway connecting ribosomal perturbations and certain aspects of growth and development. Unlike animals, however, plants have neither p53 nor MDM2 family proteins. Then the question arises whether plant cells have a nucleolar stress response pathway. In recent years, it has been reported that several members of the plant-specific transcription factor family NAC play critical roles in the pathways responsive to various cellular stresses. In this mini review, we outline the plant cellular stress response pathways involving NAC transcription factors with reference to the p53-MDM2-dependent pathways of animal cells, and discuss the possible involvement of a plant-unique, NAC-mediated pathway in the nucleolar stress response in plants.

Effect of Heat Stress on Reproduction in Dairy Cows: Insights into the Cellular and Molecular Responses of the Oocyte.

PubMed

Roth, Zvi

2017-02-08

Among the components of the female reproductive tract, the ovarian pool of follicles and their enclosed oocytes are highly sensitive to hyperthermia. Heat-induced alterations in small antral follicles can be expressed later as compromised maturation and developmental capacity of the ovulating oocyte. This review summarizes the most up-to-date information on the effects of heat stress on the oocyte with an emphasis on unclear points and open questions, some of which might involve new research directions, for instance, whether preantral follicles are heat resistant. The review focuses on the follicle-enclosed oocytes, provides new insights into the cellular and molecular responses of the oocyte to elevated temperature, points out the role of the follicle microenvironment, and discusses some mechanisms that might underlie oocyte impairment. Mechanisms include nuclear and cytoplasmic maturation, mitochondrial function, apoptotic pathways, and oxidative stress. Understanding the mechanism by which heat stress compromises fertility might enable development of new strategies to mitigate its effects.

MagR Alone Is Insufficient to Confer Cellular Calcium Responses to Magnetic Stimulation

PubMed Central

Pang, Keliang; You, He; Chen, Yanbo; Chu, Pengcheng; Hu, Meiqin; Shen, Jianying; Guo, Wei; Xie, Can; Lu, Bai

2017-01-01

Magnetic manipulation of cell activity offers advantages over optical manipulation but an ideal tool remains elusive. The MagR protein was found through its interaction with cryptochrome (Cry) and the protein in solution appeared to respond to magnetic stimulation (MS). After we initiated an investigation on the specific role of MagR in cellular response to MS, a subsequent study claimed that MagR expression alone could achieve cellular activation by MS. Here we report that despite systematically testing different ways of measuring intracellular calcium and different MS protocols, it was not possible to detect any cellular or neuronal responses to MS in MagR-expressing HEK cells or primary neurons from the dorsal root ganglion and the hippocampus. By contrast, in neurons co-expressing MagR and channelrhodopin, optical but not MS increased calcium influx in hippocampal neurons. Our results indicate that MagR alone is not sufficient to confer cellular magnetic responses. PMID:28360843

Cellular responses to recurrent pentylenetetrazole-induced seizures in the adult zebrafish brain

PubMed Central

Duy, Phan Q; Berberoglu, Michael A; Beattie, Christine E; Hall, Charles W

2017-01-01

A seizure is a sustained increase in brain electrical activity that can result in loss of consciousness and injury. Understanding how the brain responds to seizures is important for development of new treatment strategies for epilepsy, a neurological condition characterized by recurrent and unprovoked seizures. Pharmacological induction of seizures in rodent models results in a myriad of cellular alterations, including inflammation, angiogenesis, and adult neurogenesis. The purpose of this study is to investigate the cellular responses to recurrent pentylenetetrazole seizures in the adult zebrafish brain. We subjected zebrafish to five once daily pentylenetetrazole induced seizures and characterized the cellular consequences of these seizures. In response to recurrent seizures, we found histologic evidence of vasodilatation, perivascular leukocyte egress and leukocyte proliferation suggesting seizure-induced acute CNS inflammation. We also found evidence of increased proliferation, neurogenesis, and reactive gliosis. Collectively, our results suggest that the cellular responses to seizures in the adult zebrafish brain are similar to those observed in mammalian brains. PMID:28238851

Roles of microRNA in the immature immune system of neonates.

PubMed

Yu, Hong-Ren; Huang, Lien-Hung; Li, Sung-Chou

2018-06-13

Neonates have an immature immune system; therefore, their immune activities are different from the activities of adult immune systems. Such differences between neonates and adults are reflected by cell population constitutions, immune responses, cytokine production, and the expression of cellular/humoral molecules, which contribute to the specific neonatal microbial susceptibility and atopic properties. MicroRNAs (miRNAs) have been discovered to modulate many aspects of immune responses. Herein, we summarize the distinct manifestations of the neonatal immune system, including cellular and non-cellular components. We also review the current findings on the modulatory effects of miRNAs on the neonatal immune system. These findings suggest that miRNAs have the potential to be useful therapeutic targets for certain infection or inflammatory conditions by modulating the neonatal immune system. In the future, we need a more comprehensive understanding in regard to miRNAs and how they modulate specific immune cells in neonates. Copyright © 2018. Published by Elsevier B.V.

Plasmodesmata in integrated cell signalling: insights from development and environmental signals and stresses

PubMed Central

Sager, Ross; Lee, Jung-Youn

2014-01-01

To survive as sedentary organisms built of immobile cells, plants require an effective intercellular communication system, both locally between neighbouring cells within each tissue and systemically across distantly located organs. Such a system enables cells to coordinate their intracellular activities and produce concerted responses to internal and external stimuli. Plasmodesmata, membrane-lined intercellular channels, are essential for direct cell-to-cell communication involving exchange of diffusible factors, including signalling and information molecules. Recent advances corroborate that plasmodesmata are not passive but rather highly dynamic channels, in that their density in the cell walls and gating activities are tightly linked to developmental and physiological processes. Moreover, it is becoming clear that specific hormonal signalling pathways play crucial roles in relaying primary cellular signals to plasmodesmata. In this review, we examine a number of studies in which plasmodesmal structure, occurrence, and/or permeability responses are found to be altered upon given cellular or environmental signals, and discuss common themes illustrating how plasmodesmal regulation is integrated into specific cellular signalling pathways. PMID:25262225

Cellular and Molecular Mechanisms of Action of Transcranial Direct Current Stimulation: Evidence from In Vitro and In Vivo Models

PubMed Central

Pelletier, Simon J.

2015-01-01

Transcranial direct current stimulation is a noninvasive technique that has been experimentally tested for a number of psychiatric and neurological conditions. Preliminary observations suggest that this approach can indeed influence a number of cellular and molecular pathways that may be disease relevant. However, the mechanisms of action underlying its beneficial effects are largely unknown and need to be better understood to allow this therapy to be used optimally. In this review, we summarize the physiological responses observed in vitro and in vivo, with a particular emphasis on cellular and molecular cascades associated with inflammation, angiogenesis, neurogenesis, and neuroplasticity recruited by direct current stimulation, a topic that has been largely neglected in the literature. A better understanding of the neural responses to transcranial direct current stimulation is critical if this therapy is to be used in large-scale clinical trials with a view of being routinely offered to patients suffering from various conditions affecting the central nervous system. PMID:25522391

Manipulating the mitochondria activity in human hepatic cell line Huh7 by low-power laser irradiation

PubMed Central

Lynnyk, Anna; Lunova, Mariia; Jirsa, Milan; Egorova, Daria; Kulikov, Andrei; Kubinová, Šárka; Lunov, Oleg; Dejneka, Alexandr

2018-01-01

Low-power laser irradiation of red light has been recognized as a promising tool across a vast variety of biomedical applications. However, deep understanding of the molecular mechanisms behind laser-induced cellular effects remains a significant challenge. Here, we investigated mechanisms involved in the death process in human hepatic cell line Huh7 at a laser irradiation. We decoupled distinct cell death pathways targeted by laser irradiations of different powers. Our data demonstrate that high dose laser irradiation exhibited the highest levels of total reactive oxygen species production, leading to cyclophilin D-related necrosis via the mitochondrial permeability transition. On the contrary, low dose laser irradiation resulted in the nuclear accumulation of superoxide and apoptosis execution. Our findings offer a novel insight into laser-induced cellular responses, and reveal distinct cell death pathways triggered by laser irradiation. The observed link between mitochondria depolarization and triggering ROS could be a fundamental phenomenon in laser-induced cellular responses. PMID:29541521

Quantitative analysis of circadian single cell oscillations in response to temperature

PubMed Central

Kramer, Achim; Herzel, Hanspeter

2018-01-01

Body temperature rhythms synchronize circadian oscillations in different tissues, depending on the degree of cellular coupling: the responsiveness to temperature is higher when single circadian oscillators are uncoupled. So far, the role of coupling in temperature responsiveness has only been studied in organotypic tissue slices of the central circadian pacemaker, because it has been assumed that peripheral target organs behave like uncoupled multicellular oscillators. Since recent studies indicate that some peripheral tissues may exhibit cellular coupling as well, we asked whether peripheral network dynamics also influence temperature responsiveness. Using a novel technique for long-term, high-resolution bioluminescence imaging of primary cultured cells, exposed to repeated temperature cycles, we were able to quantitatively measure period, phase, and amplitude of central (suprachiasmatic nuclei neuron dispersals) and peripheral (mouse ear fibroblasts) single cell oscillations in response to temperature. Employing temperature cycles of different lengths, and different cell densities, we found that some circadian characteristics appear cell-autonomous, e.g. period responses, while others seem to depend on the quality/degree of cellular communication, e.g. phase relationships, robustness of the oscillation, and amplitude. Overall, our findings indicate a strong dependence on the cell’s ability for intercellular communication, which is not only true for neuronal pacemakers, but, importantly, also for cells in peripheral tissues. Hence, they stress the importance of comparative studies that evaluate the degree of coupling in a given tissue, before it may be used effectively as a target for meaningful circadian manipulation. PMID:29293562

Recombinant proteins of Zaire ebolavirus induce potent humoral and cellular immune responses and protect against live virus infection in mice.

PubMed

Lehrer, Axel T; Wong, Teri-Ann S; Lieberman, Michael M; Humphreys, Tom; Clements, David E; Bakken, Russell R; Hart, Mary Kate; Pratt, William D; Dye, John M

2018-05-24

Infections with filoviruses in humans are highly virulent, causing hemorrhagic fevers which result in up to 90% mortality. In addition to natural infections, the ability to use these viruses as bioterrorist weapons is of significant concern. Currently, there are no licensed vaccines or therapeutics available to combat these infections. The pathogenesis of disease involves the dysregulation of the host's immune system, which results in impairment of the innate and adaptive immune responses, with subsequent development of lymphopenia, thrombocytopenia, hemorrhage, and death. Questions remain with regard to the few survivors of infection, who manage to mount an effective adaptive immune response. These questions concern the humoral and cellular components of this response, and whether such a response can be elicited by an appropriate prophylactic vaccine. The data reported herein describe the production and evaluation of a recombinant subunit Ebola virus vaccine candidate consisting of insect cell expressed Zaire ebolavirus (EBOV) surface glycoprotein (GP) and the matrix proteins VP24 and VP40. The recombinant subunit proteins are shown to be highly immunogenic in mice, yielding both humoral and cellular responses, as well as highly efficacious, providing up to 100% protection against a lethal challenge with live virus. These results demonstrate proof of concept for such a recombinant non-replicating vaccine candidate in the mouse model of EBOV which helps to elucidate immune correlates of protection and warrants further development. Copyright © 2017 Elsevier Ltd. All rights reserved.

A single dose of inactivated hepatitis A vaccine promotes HAV-specific memory cellular response similar to that induced by a natural infection.

PubMed

Melgaço, Juliana Gil; Morgado, Lucas Nóbrega; Santiago, Marta Almeida; Oliveira, Jaqueline Mendes de; Lewis-Ximenez, Lia Laura; Hasselmann, Bárbara; Cruz, Oswaldo Gonçalves; Pinto, Marcelo Alves; Vitral, Claudia Lamarca

2015-07-31

Based on current studies on the effects of single dose vaccines on antibody production, Latin American countries have adopted a single dose vaccine program. However, no data are available on the activation of cellular response to a single dose of hepatitis A. Our study investigated the functional reactivity of the memory cell phenotype after hepatitis A virus (HAV) stimulation through administration of the first or second dose of HAV vaccine and compared the response to that of a baseline group to an initial natural infection. Proliferation assays showed that the first vaccine dose induced HAV-specific cellular response; this response was similar to that induced by a second dose or an initial natural infection. Thus, from the first dose to the second dose, increase in the frequencies of classical memory B cells, TCD8 cells, and central memory TCD4 and TCD8 cells were observed. Regarding cytokine production, increased IL-6, IL-10, TNF, and IFNγ levels were observed after vaccination. Our findings suggest that a single dose of HAV vaccine promotes HAV-specific memory cell response similar to that induced by a natural infection. The HAV-specific T cell immunity induced by primary vaccination persisted independently of the protective plasma antibody level. In addition, our results suggest that a single dose immunization system could serve as an alternative strategy for the prevention of hepatitis A in developing countries. Copyright © 2015 Elsevier Ltd. All rights reserved.

Longevity of duodenal and peripheral T-cell and humoral responses to live-attenuated Salmonella Typhi strain Ty21a.

PubMed

Pennington, Shaun H; Ferreira, Daniela M; Reiné, Jesús; Nyirenda, Tonney S; Thompson, Ameeka L; Hancock, Carole A; Wright, Angela D; Gordon, Stephen B; Gordon, Melita A

2018-06-26

We have previously demonstrated that polyfunctional Ty21a-responsive CD4 + and CD8 + T cells are generated at the duodenal mucosa 18 days following vaccination with live-attenuated S. Typhi (Ty21a). The longevity of cellular responses has been assessed in peripheral blood, but persistence of duodenal responses is unknown. We vaccinated eight healthy adults with Ty21a. Peripheral blood and duodenal samples were acquired after a median of 1.5 years (ranging from 1.1 to 3.7 years) following vaccination. Cellular responses were assessed in peripheral blood and at the duodenal mucosa by flow cytometry. Levels of IgG and IgA were also assessed in peripheral blood by enzyme-linked immunosorbent assay. No T-cell responses were observed at the duodenal mucosa, but CD4 + T-cell responses to Ty21a and FliC were observed in peripheral blood. Peripheral anti-lipopolysaccharide IgG and IgA responses were also observed. Early immunoglobulin responses were not associated with the persistence of long-term cellular immune responses. Early T-cell responses which we have previously observed at the duodenal mucosa 18 days following oral vaccination with Ty21a could not be detected at a median of 1.5 years. Peripheral responses were observed at this time. Immunoglobulin responses observed shortly after vaccination were not associated with cellular immune responses at 1.5 years, suggesting that the persistence of cellular immunity is not associated with the strength of the initial humoral response to vaccination. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Physically-Induced Cytoskeleton Remodeling of Cells in Three-Dimensional Culture

PubMed Central

Lee, Sheng-Lin; Nekouzadeh, Ali; Butler, Boyd; Pryse, Kenneth M.; McConnaughey, William B.; Nathan, Adam C.; Legant, Wesley R.; Schaefer, Pascal M.; Pless, Robert B.

2012-01-01

Characterizing how cells in three-dimensional (3D) environments or natural tissues respond to biophysical stimuli is a longstanding challenge in biology and tissue engineering. We demonstrate a strategy to monitor morphological and mechanical responses of contractile fibroblasts in a 3D environment. Cells responded to stretch through specific, cell-wide mechanisms involving staged retraction and reinforcement. Retraction responses occurred for all orientations of stress fibers and cellular protrusions relative to the stretch direction, while reinforcement responses, including extension of cellular processes and stress fiber formation, occurred predominantly in the stretch direction. A previously unreported role of F-actin clumps was observed, with clumps possibly acting as F-actin reservoirs for retraction and reinforcement responses during stretch. Responses were consistent with a model of cellular sensitivity to local physical cues. These findings suggest mechanisms for global actin cytoskeleton remodeling in non-muscle cells and provide insight into cellular responses important in pathologies such as fibrosis and hypertension. PMID:23300512

Fingerprinting the reactive toxicity pathways of 50 drinking water disinfection by-products.

PubMed

Stalter, Daniel; O'Malley, Elissa; von Gunten, Urs; Escher, Beate I

2016-03-15

A set of nine in vitro cellular bioassays indicative of different stages of the cellular toxicity pathway was applied to 50 disinfection by-products (DBPs) to obtain a better understanding of the commonalities and differences in the molecular mechanisms of reactive toxicity of DBPs. An Eschericia coli test battery revealed reactivity towards proteins/peptides for 64% of the compounds. 98% activated the NRf2-mediated oxidative stress response and 68% induced an adaptive stress response to genotoxic effects as indicated by the activation of the tumor suppressor protein p53. All DBPs reactive towards DNA in the E. coli assay and activating p53 also induced oxidative stress, confirming earlier studies that the latter could trigger DBP's carcinogenicity. The energy of the lowest unoccupied molecular orbital ELUMO as reactivity descriptor was linearly correlated with oxidative stress induction for trihalomethanes (r(2)=0.98) and haloacetamides (r(2)=0.58), indicating that potency of these DBPs is connected to electrophilicity. However, the descriptive power was poor for haloacetic acids (HAAs) and haloacetonitriles (r(2) (<) 0.06). For HAAs, we additionally accounted for speciation by including the acidity constant with ELUMO in a two-parameter multiple linear regression model. This increased r(2) to >0.80, indicating that HAAs' potency is connected to both, electrophilicity and speciation. Based on the activation of oxidative stress response and the soft electrophilic character of most tested DBPs we hypothesize that indirect genotoxicity-e.g., through oxidative stress induction and/or enzyme inhibition-is more plausible than direct DNA damage for most investigated DBPs. The results provide not only a mechanistic understanding of the cellular effects of DBPs but the effect concentrations may also serve to evaluate mixture effects of DBPs in water samples. Copyright © 2016 Elsevier Ltd. All rights reserved.

Revisiting structure-property relationship of pH-responsive polymers for drug delivery applications.

PubMed

Bazban-Shotorbani, Salime; Hasani-Sadrabadi, Mohammad Mahdi; Karkhaneh, Akbar; Serpooshan, Vahid; Jacob, Karl I; Moshaverinia, Alireza; Mahmoudi, Morteza

2017-05-10

pH-responsive polymers contain ionic functional groups as pendants in their structure. The total number of charged groups on polymer chains determines the overall response of the system to changes in the external pH. This article reviews various pH-responsive polymers classified as polyacids (e.g., carboxylic acid based polymers, sulfonamides, anionic polysaccharides, and anionic polypeptides) and polybases (e.g., polyamines, pyridine and imidazole containing polymers, cationic polysaccharides, and cationic polypeptides). We correlate the pH variations in the body at the organ level (e.g., gastrointestinal tract and vaginal environment), tissue level (e.g., cancerous and inflamed tissues), and cellular level (e.g., sub-cellular organelles), with the intrinsic properties of pH-responsive polymers. This knowledge could help to select more effective ('smart') polymeric systems based on the biological target. Considering the pH differences in the body, various drug delivery systems can be designed by utilizing smart biopolymeric compounds with the required pH-sensitivity. We also review the pharmaceutical application of pH-responsive polymeric carriers including hydrogels, polymer-drug conjugates, micelles, dendrimers, and polymersomes. © 2016.

Towards the regulation of aerosol emissions by their potential health impact: Assessing adverse effects of aerosols from wood combustion and ship diesel engine emissions by combining comprehensive data on the chemical composition and their toxicological effects on human lung cells

NASA Astrophysics Data System (ADS)

Zimmermann, R.; Streibel, T.; Dittmar, G.; Kanashova, T.; Buters, J.; Öder, S.; Paur, H. R.; Dilger, M.; Weiss, C.; Harndorf, H.; Stengel, B.; Hirvonen, M. R.; Jokiniemi, J.; Hiller, K.; Sapcariu, S.; Sippula, O.; Orasche, J.; Müller, L.; Rheda, A.; Passig, J.; Radischat, C.; Czech, H.; Tiita, P.; Jalava, P.; Kasurinen, S.; Schwemer, T.; Yli-Prilä, P.; Tissari, J.; Lamberg, H.; Schnelle-Kreis, J.

2014-12-01

Ship engine emissions are important regarding lung and cardiovascular diseases in coastal regions worldwide. Bio mass burning is made responsible for adverse health effects in many cities and rural regions. The Virtual Helmholtz Institute-HICE (www.hice-vi.eu) addresses chemical & physical properties and health effects of anthropogenic combustion emissions. Typical lung cell responses to combustion aerosols include inflammation and apoptosis, but a molecular link with the specific chemical composition in particular of ship emissions has not been established. Through an air-liquid interface exposure system (ALI), we exposed human lung cells at-site to exhaust fumes from a ship engine running on common heavy fuel oil (HFO) and cleaner-burning diesel fuel (DF) as well as to emissions of wood combustion compliances. A special field deployable ALI-exposition system and a mobile S2-biological laboratory were developed for this study. Human alveolar basal epithelial cells (A549 etc.) are ALI-exposed to fresh, diluted (1:40-1:100) combustion aerosols and subsequently were toxicologically and molecular-biologically characterized. Advanced chemical analyses of the exhaust aerosols were combined with transcriptional, proteomic and metabolomic profiling to characterise the cellular responses. The HFO ship emissions contained high concentrations of toxic compounds (transition metals, organic toxicants) and particle masses. The cellular responses included inflammation and oxidative stress. Surprisingly, the DF ship emissions, which predominantly contain rather "pure" carbonaceous soot and much less known toxicants, induced significantly broader biological effects, affecting essential cellular pathways (e.g., mitochondrial function and intracellular transport). Therefore the use of distillate fuels for shipping (this is the current emission reduction strategy of the IMO) appears insufficient for diminishing health effects. The study suggests rather reducing the particle emissions by secondary measures (filters) than shifting the fuel. In the case of wood combustion the reduction of soot and carcinogenic aromatic compounds is suggested. However, for both sources (wood and ship diesel) we found that effects of the gaseous pollutants (e.g. aldehydes) are potentially problematic.

The A2b adenosine receptor antagonist PSB-603 promotes oxidative phosphorylation and ROS production in colorectal cancer cells via adenosine receptor-independent mechanism.

PubMed

Mølck, Christina; Ryall, James; Failla, Laura M; Coates, Janine L; Pascussi, Jean-Marc; Heath, Joan K; Stewart, Gregory; Hollande, Frédéric

2016-12-01

Adenosine is a multifaceted regulator of tumor progression. It modulates immune cell activity as well as acting directly on tumor cells. The A 2b adenosine receptor (A 2b -AR) is thought to be an important mediator of these effects. In this study we sought to analyze the contribution of the A 2b -AR to the behavior of colorectal cancer cells. The A 2b -AR antagonist PSB-603 changed cellular redox state without affecting cellular viability. Quantification of cellular bioenergetics demonstrated that PSB-603 increased basal oxygen consumption rates, indicative of enhanced mitochondrial oxidative phosphorylation. Unexpectedly, pharmacological and genetic approaches to antagonize AR-related signalling of PSB-603 did not abolish the response, suggesting that it was AR-independent. PSB-603 also induced acute increases in reactive oxygen species, and PSB-603 synergized with chemotherapy treatment to increase colorectal cancer cell death, consistent with the known link between cellular metabolism and chemotherapy response. PSB-603 alters cellular metabolism in colorectal cancer cells and increases their sensitivity to chemotherapy. Although requiring more mechanistic insight into its A 2b -AR-independent activity, our results show that PSB-603 may have clinical value as an anti-colorectal cancer therapeutic. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

High-Concentrate Diet-Induced Change of Cellular Metabolism Leads to Decreases of Immunity and Imbalance of Cellular Activities in Rumen Epithelium.

PubMed

Lu, Zhongyan; Shen, Hong; Shen, Zanming

2018-01-01

In animals, the immune and cellular processes of tissue largely depend on the status of local metabolism. However, in the rumen epithelium, how the cellular metabolism affects epithelial immunity, and cellular processes, when the diet is switched from energy-rich to energy-excess status, with regard to animal production and health, have not as yet been reported. RNA-seq was applied to compare the biological processes altered by an increase of dietary concentration from 10% to 35% with those altered by an increase of dietary concentration from 35% to 65% (dietary concentrate: the non-grass component in diet, including corn, soya bean meal and additive. High concentrate diet composed of 35% grass, 55% corn, 8% soya bean meal and 2% additive). In addition to the functional analysis of enriched genes in terms of metabolism, the immune system, and cellular process, the highly correlated genes to the enriched metabolism genes were identified, and the function and signaling pathways related to the differentially expressed neighbors were compared among the groups. The variation trends of molar proportions of ruminal SCFAs and those of enriched pathways belonging to metabolism, immune system, and cellular process were altered with the change of diets. With regard to metabolism, lipid metabolism and amino acid metabolism were most affected. According to the correlation analysis, both innate and adaptive immune responses were promoted by the metabolism genes enriched under the 65% concentrate diet. However, the majority of immune responses were suppressed under the 35% concentrate diet. Moreover, the exclusive upregulation of cell growth and dysfunction of cellular transport and catabolism were induced by the metabolism genes enriched under the 65% concentrate diet. On the contrary, a balanced regulation of cellular processes was detected under the 35% concentrate diet. These results indicated that the alterations of cellular metabolism promote the alterations in cellular immunity, repair, and homeostasis in the rumen epithelium, thereby leading to the switch of concentrate effects from positive to negative with regard to animal production and health. © 2018 The Author(s). Published by S. Karger AG, Basel.

Effect of calcium carbonate particle shape on phagocytosis and pro-inflammatory response in differentiated THP-1 macrophages.

PubMed

Tabei, Yosuke; Sugino, Sakiko; Eguchi, Kenichiro; Tajika, Masahiko; Abe, Hiroko; Nakajima, Yoshihiro; Horie, Masanori

2017-08-19

Phagocytosis is a physiological process used by immune cells such as macrophages to actively ingest and destroy foreign pathogens and particles. It is the cellular process that leads to the failure of drug delivery carriers because the drug carriers are cleared by immune cells before reaching their target. Therefore, clarifying the mechanism of particle phagocytosis would have a significant implication for both fundamental understanding and biomedical engineering. As far as we know, the effect of particle shape on biological response has not been fully investigated. In the present study, we investigated the particle shape-dependent cellular uptake and biological response of differentiated THP-1 macrophages by using calcium carbonate (CaCO 3 )-based particles as a model. Transmission electron microscopy analysis revealed that the high uptake of needle-shaped CaCO 3 particles by THP-1 macrophages because of their high phagocytic activity. In addition, the THP-1 macrophages exposed to needle-shaped CaCO 3 accumulated a large amount of calcium in the intracellular matrix. The enhanced release of interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNF-α) by the THP-1 macrophages suggested that the needle-shaped CaCO 3 particles trigger a pro-inflammatory response. In contrast, no pro-inflammatory response was induced in undifferentiated THP-1 monocytes exposed to either needle- or cuboidal-shaped CaCO 3 particles, probably because of their low phagocytic activity. We also found that phosphate-coated particles efficiently repressed cellular uptake and the resulting pro-inflammatory response in both THP-1 macrophages and primary peritoneal macrophages. Our results indicate that the pro-inflammatory response of macrophages upon exposure to CaCO 3 particles is shape- and surface property-dependent, and is mediated by the intracellular accumulation of calcium ions released from phagocytosed CaCO 3 particles. Copyright © 2017 Elsevier Inc. All rights reserved.

Three-Year Durability of Immune Responses Induced by HIV-DNA and HIV-Modified Vaccinia Virus Ankara and Effect of a Late HIV-Modified Vaccinia Virus Ankara Boost in Tanzanian Volunteers.

PubMed

Joachim, Agricola; Munseri, Patricia J; Nilsson, Charlotta; Bakari, Muhammad; Aboud, Said; Lyamuya, Eligius F; Tecleab, Teghesti; Liakina, Valentina; Scarlatti, Gabriella; Robb, Merlin L; Earl, Patricia L; Moss, Bernard; Wahren, Britta; Mhalu, Fred; Ferrari, Guido; Sandstrom, Eric; Biberfeld, Gunnel

2017-08-01

We explored the duration of immune responses and the effect of a late third HIV-modified vaccinia virus Ankara (MVA) boost in HIV-DNA primed and HIV-MVA boosted Tanzanian volunteers. Twenty volunteers who had previously received three HIV-DNA and two HIV-MVA immunizations were given a third HIV-MVA immunization 3 years after the second HIV-MVA boost. At the time of the third HIV-MVA, 90% of the vaccinees had antibodies to HIV-1 subtype C gp140 (median titer 200) and 85% to subtype B gp160 (median titer 100). The majority of vaccinees had detectable antibody-dependent cellular cytotoxicity (ADCC)-mediating antibodies, 70% against CRF01_AE virus-infected cells (median titer 239) and 84% against CRF01_AE gp120-coated cells (median titer 499). A high proportion (74%) of vaccinees had IFN-γ ELISpot responses, 63% to Gag and 42% to Env, 3 years after the second HIV-MVA boost. After the third HIV-MVA, there was an increase in Env-binding antibodies and ADCC-mediating antibodies relative to the response seen at the time of the third HIV-MVA vaccination, p < .0001 and p < .05, respectively. The frequency of IFN-γ ELISpot responses increased to 95% against Gag or Env and 90% to both Gag and Env, p = .064 and p = .002, respectively. In conclusion, the HIV-DNA prime/HIV-MVA boost regimen elicited potent antibody and cellular immune responses with remarkable durability, and a third HIV-MVA immunization significantly boosted both antibody and cellular immune responses relative to the levels detected at the time of the third HIV-MVA, but not to higher levels than after the second HIV-MVA.

Cellular Response to Bleomycin-Induced DNA Damage in Human Fibroblast Cells in Space

NASA Technical Reports Server (NTRS)

Lu, Tao; Zhang, Ye; Wong, Michael; Stodieck, Louis; Karouia, Fathi; Wu, Honglu

2015-01-01

Living organisms are constantly exposed to space radiation that consists of energetic protons and other heavier charged particles. Whether spaceflight factors, microgravity in particular, affects on the cellular response to DNA damage induced by exposures to radiation or other toxic chemicals will have an impact on the radiation risks for the astronauts, as well as on the mutation rate in microorganisms, is still an open question. Although the possible synergistic effects of space radiation and other spaceflight factors have been investigated since the early days of the human space program, the published results were mostly conflicting and inconsistent. To investigate the effects of spaceflight on the cellular response to DNA damages, human fibroblast cells flown to the International Space Station (ISS) were treated with bleomycin for three hours in the true microgravity environment, which induces DNA damages including the double strand breaks (DSB) similar to the ionizing radiation. Damage in the DNA was measured by the phosphorylation of a histone protein H2AX (-H2AX), which showed slightly more foci in the cells on ISS than in the ground control. The expression of genes involved in the DNA damage response was also analyzed using the PCR array. Although a number of the genes, including CDKN1A and PCNA, were significantly altered in the cells after bleomycin treatment, no significant difference in the expression profile of DNA damage response genes was found between the flight and ground samples. At the time of the bleomycin treatment, the cells on the ISS were found to be proliferating faster than the ground control as measured by the percentage of cells containing positive Ti-67 signals. Our results suggested that the difference in -H2AX between flight and ground was due to the faster growth rate of the cells in space, but spaceflight did not affect the response of the DNA damage response genes to bleomycin treatment.

STAT3 balances myocyte hypertrophy vis-à-vis autophagy in response to Angiotensin II by modulating the AMPKα/mTOR axis.

PubMed

Chen, Lei; Zhao, Lin; Samanta, Anweshan; Mahmoudi, Seyed Morteza; Buehler, Tanner; Cantilena, Amy; Vincent, Robert J; Girgis, Magdy; Breeden, Joshua; Asante, Samuel; Xuan, Yu-Ting; Dawn, Buddhadeb

2017-01-01

Signal transducers and activators of transcription 3 (STAT3) is known to participate in various cardiovascular signal transduction pathways, including those responsible for cardiac hypertrophy and cytoprotection. However, the role of STAT3 signaling in cardiomyocyte autophagy remains unclear. We tested the hypothesis that Angiotensin II (Ang II)-induced cardiomyocyte hypertrophy is effected, at least in part, through STAT3-mediated inhibition of cellular autophagy. In H9c2 cells, Ang II treatment resulted in STAT3 activation and cellular hypertrophy in a dose-dependent manner. Ang II enhanced autophagy, albeit without impacting AMPKα/mTOR signaling or cellular ADP/ATP ratio. Pharmacologic inhibition of STAT3 with WP1066 suppressed Ang II-induced myocyte hypertrophy and mRNA expression of hypertrophy-related genes ANP and β-MHC. These molecular events were recapitulated in cells with STAT3 knockdown. Genetic or pharmacologic inhibition of STAT3 significantly increased myocyte ADP/ATP ratio and enhanced autophagy through AMPKα/mTOR signaling. Pharmacologic activation and inhibition of AMPKα attenuated and exaggerated, respectively, the effects of Ang II on ANP and β-MHC gene expression, while concomitant inhibition of STAT3 accentuated the inhibition of hypertrophy. Together, these data indicate that novel nongenomic effects of STAT3 influence myocyte energy status and modulate AMPKα/mTOR signaling and autophagy to balance the transcriptional hypertrophic response to Ang II stimulation. These findings may have significant relevance for various cardiovascular pathological processes mediated by Ang II signaling.

Sleep deprivation and activation of morning levels of cellular and genomic markers of inflammation.

PubMed

Irwin, Michael R; Wang, Minge; Campomayor, Capella O; Collado-Hidalgo, Alicia; Cole, Steve

2006-09-18

Inflammation is associated with increased risk of cardiovascular disorders, arthritis, diabetes mellitus, and mortality. The effects of sleep loss on the cellular and genomic mechanisms that contribute to inflammatory cytokine activity are not known. In 30 healthy adults, monocyte intracellular proinflammatory cytokine production was repeatedly assessed during the day across 3 baseline periods and after partial sleep deprivation (awake from 11 pm to 3 am). We analyzed the impact of sleep loss on transcription of proinflammatory cytokine genes and used DNA microarray analyses to characterize candidate transcription-control pathways that might mediate the effects of sleep loss on leukocyte gene expression. In the morning after a night of sleep loss, monocyte production of interleukin 6 and tumor necrosis factor alpha was significantly greater compared with morning levels following uninterrupted sleep. In addition, sleep loss induced a more than 3-fold increase in transcription of interleukin 6 messenger RNA and a 2-fold increase in tumor necrosis factor alpha messenger RNA. Bioinformatics analyses suggested that the inflammatory response was mediated by the nuclear factor kappaB inflammatory signaling system as well as through classic hormone and growth factor response pathways. Sleep loss induces a functional alteration of the monocyte proinflammatory cytokine response. A modest amount of sleep loss also alters molecular processes that drive cellular immune activation and induce inflammatory cytokines; mapping the dynamics of sleep loss on molecular signaling pathways has implications for understanding the role of sleep in altering immune cell physiologic characteristics. Interventions that target sleep might constitute new strategies to constrain inflammation with effects on inflammatory disease risk.

STAT3 balances myocyte hypertrophy vis-à-vis autophagy in response to Angiotensin II by modulating the AMPKα/mTOR axis

PubMed Central

Samanta, Anweshan; Mahmoudi, Seyed Morteza; Buehler, Tanner; Cantilena, Amy; Vincent, Robert J.; Girgis, Magdy; Breeden, Joshua; Asante, Samuel; Xuan, Yu-Ting

2017-01-01

Signal transducers and activators of transcription 3 (STAT3) is known to participate in various cardiovascular signal transduction pathways, including those responsible for cardiac hypertrophy and cytoprotection. However, the role of STAT3 signaling in cardiomyocyte autophagy remains unclear. We tested the hypothesis that Angiotensin II (Ang II)-induced cardiomyocyte hypertrophy is effected, at least in part, through STAT3-mediated inhibition of cellular autophagy. In H9c2 cells, Ang II treatment resulted in STAT3 activation and cellular hypertrophy in a dose-dependent manner. Ang II enhanced autophagy, albeit without impacting AMPKα/mTOR signaling or cellular ADP/ATP ratio. Pharmacologic inhibition of STAT3 with WP1066 suppressed Ang II-induced myocyte hypertrophy and mRNA expression of hypertrophy-related genes ANP and β-MHC. These molecular events were recapitulated in cells with STAT3 knockdown. Genetic or pharmacologic inhibition of STAT3 significantly increased myocyte ADP/ATP ratio and enhanced autophagy through AMPKα/mTOR signaling. Pharmacologic activation and inhibition of AMPKα attenuated and exaggerated, respectively, the effects of Ang II on ANP and β-MHC gene expression, while concomitant inhibition of STAT3 accentuated the inhibition of hypertrophy. Together, these data indicate that novel nongenomic effects of STAT3 influence myocyte energy status and modulate AMPKα/mTOR signaling and autophagy to balance the transcriptional hypertrophic response to Ang II stimulation. These findings may have significant relevance for various cardiovascular pathological processes mediated by Ang II signaling. PMID:28686615

Cellular Response to Ionizing Radiation: A MicroRNA Story

PubMed Central

Halimi, Mohammad; Asghari, S. Mohsen; Sariri, Reyhaneh; Moslemi, Dariush; Parsian, Hadi

2012-01-01

MicroRNAs (miRNAs) represent a class of small non-coding RNA molecules that regulate gene expression at the post-transcriptional level. They play a crucial role in diverse cellular pathways. Ionizing radiation (IR) is one of the most important treatment protocols for patients that suffer from cancer and affects directly or indirectly cellular integration. Recently it has been discovered that microRNA-mediated gene regulation interferes with radio-related pathways in ionizing radiation. Here, we review the recent discoveries about miRNAs in cellular response to IR. Thoroughly understanding the mechanism of miRNAs in radiation response, it will be possible to design new strategies for improving radiotherapy efficiency and ultimately cancer treatment. PMID:24551775

Assessment of humoral and cellular-mediated immune response in chickens treated with tilmicosin, florfenicol, or enrofloxacin at the time of Newcastle disease vaccination.

PubMed

Khalifeh, M S; Amawi, M M; Abu-Basha, E A; Yonis, I Bani

2009-10-01

The effect of tilmicosin, florfenicol, or enrofloxacin on humoral and cell-mediated immune response induced by Newcastle disease (ND) vaccination was evaluated in 20-wk-old specific-pathogen-free layer chickens. Humoral immunity was measured by detection of ND virus (NDV) antibody titer and anti-NDV IgG response using the hemagglutination inhibition (HI) test and ELISA, respectively, whereas cell-mediated immunity was evaluated by measurement of chicken interferon gamma (ChIFN-gamma) produced in splenocytes cell culture stimulated with concanavalin A, inactivated NDV antigen, or live attenuated La Sota strain using ELISA. Florfenicol hampered the ND antibody production measured by both HI and ELISA. Tilmicosin and enrofloxacin reduced the production of ND antibody in the first 3 wk after the last ND vaccination measured by HI test, which suggests that these antibiotics exert their effect mainly on the IgM isotype. The ND-vaccinated, but not treated group, showed an increase in ChIFN-gamma production after NDV antigen-specific stimulation above the nonstimulated cell culture, whereas this effect was masked in all the antibiotic-treated groups due to the stronger ChIFN-gamma production background value reported in the nonstimulated cell culture. In conclusion, our results showed, for the first time, that tilmicosin, florfenicol, or enrofloxacin reduced the humoral immune response and had beneficial effects on the cell-mediated immune response. In addition, we demonstrated that the combination of both inactivated and attenuated ND vaccine gave a strong immune response at both the humoral and cellular level.

T-oligo as an anticancer agent in colorectal cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wojdyla, Luke; Stone, Amanda L.; Sethakorn, Nan

Highlights: • T-oligo induces cell cycle arrest, senescence, apoptosis, and differentiation in CRC. • Treatment with T-oligo downregulates telomere-associated proteins. • T-oligo combined with an EGFR-TKI additively inhibits cellular proliferation. • T-oligo has potential as an effective therapeutic agent for CRC. - Abstract: In the United States, there will be an estimated 96,830 new cases of colorectal cancer (CRC) and 50,310 deaths in 2014. CRC is often detected at late stages of the disease, at which point there is no effective chemotherapy. Thus, there is an urgent need for effective novel therapies that have minimal effects on normal cells. T-oligo,more » an oligonucleotide homologous to the 3′-telomere overhang, induces potent DNA damage responses in multiple malignant cell types, however, its efficacy in CRC has not been studied. This is the first investigation demonstrating T-oligo-induced anticancer effects in two CRC cell lines, HT-29 and LoVo, which are highly resistant to conventional chemotherapies. In this investigation, we show that T-oligo may mediate its DNA damage responses through the p53/p73 pathway, thereby inhibiting cellular proliferation and inducing apoptosis or senescence. Additionally, upregulation of downstream DNA damage response proteins, including E2F1, p53 or p73, was observed. In LoVo cells, T-oligo induced senescence, decreased clonogenicity, and increased expression of senescence associated proteins p21, p27, and p53. In addition, downregulation of POT1 and TRF2, two components of the shelterin protein complex which protects telomeric ends, was observed. Moreover, we studied the antiproliferative effects of T-oligo in combination with an EGFR tyrosine kinase inhibitor, Gefitinib, which resulted in an additive inhibitory effect on cellular proliferation. Collectively, these data provide evidence that T-oligo alone, or in combination with other molecularly targeted therapies, has potential as an anti-cancer agent in CRC.« less

Augmentation of humoral and cellular immunity in response to Tetanus and Diphtheria toxoids by supercritical carbon dioxide extracts of Hippophae rhamnoides L. leaves.

PubMed

Jayashankar, Bindhya; Singh, Divya; Tanwar, Himanshi; Mishra, K P; Murthy, Swetha; Chanda, Sudipta; Mishra, Jigni; Tulswani, R; Misra, K; Singh, S B; Ganju, Lilly

2017-03-01

Hippophae rhamnoides L. commonly known as Seabuckthorn (SBT), a wild shrub of family Elaegnacea, has extensively used for treating various ailments like skin diseases, jaundice, asthma, lung troubles. SBT leaves have been reported to possess several pharmacological properties including immunomodulatory, antioxidant, anti-inflammatory, antimicrobial and tissue regeneration etc. The present study was undertaken to evaluate the adjuvant property of supercritical carbon dioxide extracts (SCEs 300ET and 350ET) of SBT leaves in balb/c mice immunized with Tetanus and Diphtheria toxoids. The dynamic changes in the immune response were measured in terms of humoral and cell-mediated immune responses. We have seen the effect of SCEs on immunoglobulin subtypes and secondary immune response generation. In addition, the effect of SCEs on antigen specific cellular immunity was evaluated. Our results show that SCEs 300ET and 350ET significantly enhanced antibody titers in response to both TT and DT antigens. The secondary immune response generated was significantly increased in case of TT immunized animals. SCEs also enhanced cytokine levels (IFN-γ, IL-4, TNF-α and IL-1β) and increased lymphoproliferation. Besides, both SCEs did not show any toxic effects. Therefore, the study suggests that SCEs are safe and have potent immunostimulatory activity and hence, seems to be a promising balanced Th1 and Th2 directing immunological adjuvant for various veterinary as well as human vaccines. Copyright © 2017. Published by Elsevier B.V.

The nucleolus—guardian of cellular homeostasis and genome integrity.

PubMed

Grummt, Ingrid

2013-12-01

All organisms sense and respond to conditions that stress their homeostasis by downregulating the synthesis of rRNA and ribosome biogenesis, thus designating the nucleolus as the central hub in coordinating the cellular stress response. One of the most intriguing roles of the nucleolus, long regarded as a mere ribosome-producing factory, is its participation in monitoring cellular stress signals and transmitting them to the RNA polymerase I (Pol I) transcription machinery. As rRNA synthesis is a most energy-consuming process, switching off transcription of rRNA genes is an effective way of saving the energy required to maintain cellular homeostasis during acute stress. The Pol I transcription machinery is the key convergence point that collects and integrates a vast array of information from cellular signaling cascades to regulate ribosome production which, in turn, guides cell growth and proliferation. This review focuses on the mechanisms that link cell physiology to rDNA silencing, a prerequisite for nucleolar integrity and cell survival.

Combinatorial approaches to evaluate nanodiamond uptake and induced cellular fate

NASA Astrophysics Data System (ADS)

Eldawud, Reem; Reitzig, Manuela; Opitz, Jörg; Rojansakul, Yon; Jiang, Wenjuan; Nangia, Shikha; Zoica Dinu, Cerasela

2016-02-01

Nanodiamonds (NDs) are an emerging class of engineered nanomaterials that hold great promise for the next generation of bionanotechnological products to be used for drug and gene delivery, or for bio-imaging and biosensing. Previous studies have shown that upon their cellular uptake, NDs exhibit high biocompatibility in various in vitro and in vivo set-ups. Herein we hypothesized that the increased NDs biocompatibility is a result of minimum membrane perturbations and their reduced ability to induce disruption or damage during cellular translocation. Using multi-scale combinatorial approaches that simulate ND-membrane interactions, we correlated NDs real-time cellular uptake and kinetics with the ND-induced membrane fluctuations to derive energy requirements for the uptake to occur. Our discrete and real-time analyses showed that the majority of NDs internalization occurs within 2 h of cellular exposure, however, with no effects on cellular viability, proliferation or cellular behavior. Furthermore, our simulation analyses using coarse-grained models identified key changes in the energy profile, membrane deformation and recovery time, all functions of the average ND or ND-based agglomerate size. Understanding the mechanisms responsible for ND-cell membrane interactions could possibly advance their implementation in various biomedical applications.

Combinatorial approaches to evaluate nanodiamond uptake and induced cellular fate

PubMed Central

Eldawud, Reem; Reitzig, Manuela; Opitz, Jörg; Rojansakul, Yon; Jiang, Wenjuan; Nangia, Shikha; Dinu, Cerasela Zoica

2016-01-01

Nanodiamonds (NDs) are an emerging class of engineered nanomaterials that hold great promise for the next generation of bionanotechnological products to be used for drug and gene delivery, or for bio-imaging and biosensing. Previous studies have shown that upon their cellular uptake, NDs exhibit high biocompatibility in various in vitro and in vivo set-ups. Herein we hypothesized that the increased NDs biocompatibility is a result of minimum membrane perturbations and their reduced ability to induce disruption or damage during cellular translocation. Using multi-scale combinatorial approaches that simulate ND-membrane interactions, we correlated NDs real-time cellular uptake and kinetics with the ND-induced membrane fluctuations to derive energy requirements for the uptake to occur. Our discrete and real-time analyses showed that the majority of NDs internalization occurs within 2 h of cellular exposure, however, with no effects on cellular viability, proliferation or cellular behavior. Furthermore, our simulation analyses using coarse-grained models identified key changes in the energy profile, membrane deformation and recovery time, all functions of the average ND or ND-based agglomerate size. Understanding the mechanisms responsible for ND-cell membrane interactions could possibly advance their implementation in various biomedical applications. PMID:26820775

Toxicogenomic response of Pseudomonas aeruginosa to ortho-phenylphenol

PubMed Central

Nde, Chantal W; Jang, Hyeung-Jin; Toghrol, Freshteh; Bentley, William E

2008-01-01

Background Pseudomonas aeruginosa (P. aeruginosa) is the most common opportunistic pathogen implicated in nosocomial infections and in chronic lung infections in cystic fibrosis patients. Ortho-phenylphenol (OPP) is an antimicrobial agent used as an active ingredient in several EPA registered disinfectants. Despite its widespread use, there is a paucity of information on its target molecular pathways and the cellular responses that it elucidates in bacteria in general and in P. aeruginosa in particular. An understanding of the OPP-driven gene regulation and cellular response it elicits will facilitate more effective utilization of this antimicrobial and possibly lead to the development of more effective disinfectant treatments. Results Herein, we performed a genome-wide transcriptome analysis of the cellular responses of P. aeruginosa exposed to 0.82 mM OPP for 20 and 60 minutes. Our data indicated that OPP upregulated the transcription of genes encoding ribosomal, virulence and membrane transport proteins after both treatment times. After 20 minutes of exposure to 0.82 mM OPP, genes involved in the exhibition of swarming motility and anaerobic respiration were upregulated. After 60 minutes of OPP treatment, the transcription of genes involved in amino acid and lipopolysaccharide biosynthesis were upregulated. Further, the transcription of the ribosome modulation factor (rmf) and an alternative sigma factor (rpoS) of RNA polymerase were downregulated after both treatment times. Conclusion Results from this study indicate that after 20 minutes of exposure to OPP, genes that have been linked to the exhibition of anaerobic respiration and swarming motility were upregulated. This study also suggests that the downregulation of the rmf and rpoS genes may be indicative of the mechanism by which OPP causes decreases in cell viability in P. aeruginosa. Consequently, a protective response involving the upregulation of translation leading to the increased synthesis of membrane related proteins and virulence proteins is possibly induced after both treatment times. In addition, cell wall modification may occur due to the increased synthesis of lipopolysaccharide after 60 minutes exposure to OPP. This gene expression profile can now be utilized for a better understanding of the target cellular pathways of OPP in P. aeruginosa and how this organism develops resistance to OPP. PMID:18847467

Inherent X-Linked Genetic Variability and Cellular Mosaicism Unique to Females Contribute to Sex-Related Differences in the Innate Immune Response.

PubMed

Spolarics, Zoltan; Peña, Geber; Qin, Yong; Donnelly, Robert J; Livingston, David H

2017-01-01

Females have a longer lifespan and better general health than males. Considerable number of studies also demonstrated that, after trauma and sepsis, females present better outcomes as compared to males indicating sex-related differences in the innate immune response. The current notion is that differences in the immuno-modulatory effects of sex hormones are the underlying causative mechanism. However, the field remains controversial and the exclusive role of sex hormones has been challenged. Here, we propose that polymorphic X-linked immune competent genes, which are abundant in the population are important players in sex-based immuno-modulation and play a key role in causing sex-related outcome differences following trauma or sepsis. We describe the differences in X chromosome (ChrX) regulation between males and females and its consequences in the context of common X-linked polymorphisms at the individual as well as population level. We also discuss the potential pathophysiological and immune-modulatory aspects of ChrX cellular mosaicism, which is unique to females and how this may contribute to sex-biased immune-modulation. The potential confounding effects of ChrX skewing of cell progenitors at the bone marrow is also presented together with aspects of acute trauma-induced de novo ChrX skewing at the periphery. In support of the hypothesis, novel observations indicating ChrX skewing in a female trauma cohort as well as case studies depicting the temporal relationship between trauma-induced cellular skewing and the clinical course are also described. Finally, we list and discuss a selected set of polymorphic X-linked genes, which are frequent in the population and have key regulatory or metabolic functions in the innate immune response and, therefore, are primary candidates for mediating sex-biased immune responses. We conclude that sex-related differences in a variety of disease processes including the innate inflammatory response to injury and infection may be related to the abundance of X-linked polymorphic immune-competent genes, differences in ChrX regulation, and inheritance patterns between the sexes and the presence of X-linked cellular mosaicism, which is unique to females.

Inhibition of matrix metalloproteinases and toxicity of gold and platinum nanoparticles in L929 fibroblast cells.

PubMed

Hashimoto, Masanori; Yamaguchi, Satoshi; Sasaki, Jun-Ichi; Kawai, Koji; Kawakami, Hayato; Iwasaki, Yasuhiko; Imazato, Satoshi

2016-02-01

This study evaluated the inhibition of matrix metalloproteases (MMPs) and cellular responses elicited by gold (Au) and platinum (Pt) nanoparticles (NPs). The interaction of MMP-1 and NPs was evaluated using an MMP assay kit. The cultured L929 cells were exposed to various concentrations of NPs. The cellular responses to NPs were examined using a cytotoxicity assay (that evaluated cell viability and lactic dehydrogenase production), real-time polymerase chain reaction (RT-qPCR), and transmission electron microscopy. Both types of NPs, when used at concentrations above 10 μg ml(-1), inhibited MMP-1 activity. No cytotoxic effects were found when the cells were exposed to AuNPs. In contrast, PtNPs, at both 100 and 400 μg ml(-1), induced cytotoxicity. No inflammatory responses (production of interleukin-6 and tumor necrosis factor-alpha) to NPs were identified by RT-qPCR. The negative surface charge of NPs (COOH(-)) binds to the Zn(2+) of the MMP active center by chelation, leading to MMP inhibition. Gold nanoparticles are plausible candidates for MMP inhibitors in resin-bonding materials because they effectively inhibit MMP-1 activity without cytotoxic or inflammatory effects. © 2015 Eur J Oral Sci.

Methamphetamine Administration Modifies Leukocyte Proliferation and Cytokine Production in Murine Tissues

PubMed Central

Peerzada, Habibullah; Ghandi, Jay A.; Guimaraes, Allan J.; Nosanchuk, Joshua D.; Martinez, Luis R.

2013-01-01

Methamphetamine (METH) is a potent and highly addictive central nervous system (CNS) stimulant. Additionally, METH adversely impacts immunological responses, which might contribute to the higher rate and more rapid progression of certain infections in drug abusers. However no studies have shown the impact of METH on inflammation within specific organs, cellular participation and cytokine production. Using a murine model of METH administration, we demonstrated that METH modifies, with variable degrees, leukocyte recruitment and alters cellular mediators in the lungs, liver, spleen and kidneys of mice. Our findings demonstrate the pleotropic effects of METH on the immune response within diverse tissues. These alterations have profound implications on tissue homeostasis and the capacity of the host to respond to diverse insults, including invading pathogens. PMID:23518444

T7 phage displaying latent membrane protein 1 of Epstein-Barr virus elicits humoral and cellular immune responses in rats.

PubMed

Gao, J; Liu, Z; Huang, M; Li, X; Wang, Z

2011-01-01

The latent membrane protein 1 (LMP1) encoded by Epstein-Barr virus (EBV) has become a potential target in EBV-associated tumor prevention and treatment due to its multiple biological effects. In this study, the recombinant T7 phage displaying full-length LMP1 protein was cloned and used as an immunogen to immunize rats. Results of flow cytometry, Western blot analysis, and ELISA confirmed that both humoral and cellular immune responses were elicited in the immunized rats. Our data suggested that T7 phage was an efficient antigen carrier. The recombinant T7-LMP1 phage reconstitutes the antigenic and immunogenic properties of LMP1 and can serve as a vaccine against EBV.

Effect of Small-Scale Turbulence on the Physiology and Morphology of Two Bloom-Forming Cyanobacteria.

PubMed

Xiao, Yan; Li, Zhe; Li, Chao; Zhang, Zhen; Guo, Jinsong

2016-01-01

The main goal of the present work is to test the hypothesis that small-scale turbulence affected physiological activities and the morphology of cyanobacteria in high turbulence environments. Using quantified turbulence in a stirring device, we conducted one set of experiments on cultures of two strains of cyanobacteria with different phenotypes; i.e., unicellular Microcystis flos-aquae and colonial Anabaena flos-aquae. The effect of small-scale turbulence examined varied from 0 to 8.01×10-2 m2s-3, covering the range of turbulence intensities experienced by cyanobacteria in the field. The results of photosynthesis activity and the cellular chlorophyll a in both strains did not change significantly among the turbulence levels, indicating that the potential indirect effects of a light regime under the gradient of turbulent mixing could be ignored. However, the experiments demonstrated that small-scale turbulence significantly modulated algal nutrient uptake and growth in comparison to the stagnant control. Cellular N and C of the two stains showed approximately the same responses, resulting in a similar pattern of C/N ratios. Moreover, the change in the phosphate uptake rate was similar to that of growth in two strains, which implied that growth characteristic responses to turbulence may be dependent on the P strategy, which was correlated with accumulation of polyphosphate. Additionally, our results also showed the filament length of A. flos-aquae decreased in response to high turbulence, which could favor enhancement of the nutrient uptake. These findings suggested that both M. flos-aquae and A. flos-aquae adjust their growth rates in response to turbulence levels in the ways of asynchronous cellular stoichiometry of C, N, and P, especially the phosphorus strategy, to improve the nutrient application efficiency. The fact that adaptation strategies of cyanobacteria diversely to turbulence depending on their physiological conditions presents a good example to understand the direct cause-effect relationship between hydrodynamic forces and algae.

Computational modeling of radiobiological effects in bone metastases for different radionuclides.

PubMed

Liberal, Francisco D C Guerra; Tavares, Adriana Alexandre S; Tavares, João Manuel R S

2017-06-01

Computational simulation is a simple and practical way to study and to compare a variety of radioisotopes for different medical applications, including the palliative treatment of bone metastases. This study aimed to evaluate and compare cellular effects modelled for different radioisotopes currently in use or under research for treatment of bone metastases using computational methods. Computational models were used to estimate the radiation-induced cellular effects (Virtual Cell Radiobiology algorithm) post-irradiation with selected particles emitted by Strontium-89 ( 89 Sr), Samarium-153 ( 153 Sm), Lutetium-177 ( 177 Lu), and Radium-223 ( 223 Ra). Cellular kinetics post-irradiation using 89 Sr β - particles, 153 Sm β -  particles, 177 Lu β -  particles and 223 Ra α particles showed that the cell response was dose- and radionuclide-dependent. 177 Lu beta minus particles and, in particular, 223 Ra alpha particles, yielded the lowest survival fraction of all investigated particles. 223 Ra alpha particles induced the highest cell death of all investigated particles on metastatic prostate cells in comparison to irradiation with β -  radionuclides, two of the most frequently used radionuclides in the palliative treatment of bone metastases in clinical routine practice. Moreover, the data obtained suggest that the used computational methods might provide some perception about cellular effects following irradiation with different radionuclides.

Geminiviruses and Plant Hosts: A Closer Examination of the Molecular Arms Race.

PubMed

Ramesh, Shunmugiah V; Sahu, Pranav P; Prasad, Manoj; Praveen, Shelly; Pappu, Hanu R

2017-09-15

Geminiviruses are plant-infecting viruses characterized by a single-stranded DNA (ssDNA) genome. Geminivirus-derived proteins are multifunctional and effective regulators in modulating the host cellular processes resulting in successful infection. Virus-host interactions result in changes in host gene expression patterns, reprogram plant signaling controls, disrupt central cellular metabolic pathways, impair plant's defense system, and effectively evade RNA silencing response leading to host susceptibility. This review summarizes what is known about the cellular processes in the continuing tug of war between geminiviruses and their plant hosts at the molecular level. In addition, implications for engineered resistance to geminivirus infection in the context of a greater understanding of the molecular processes are also discussed. Finally, the prospect of employing geminivirus-based vectors in plant genome engineering and the emergence of powerful genome editing tools to confer geminivirus resistance are highlighted to complete the perspective on geminivirus-plant molecular interactions.

Boron nitride nanotubes as vehicles for intracellular delivery of fluorescent drugs and probes.

PubMed

Niskanen, Jukka; Zhang, Issan; Xue, Yanming; Golberg, Dmitri; Maysinger, Dusica; Winnik, Françoise M

2016-01-01

To evaluate the response of cells to boron nitride nanotubes (BNNTs) carrying fluorescent probes or drugs in their inner channel by assessment of the cellular localization of the fluorescent cargo, evaluation of the in vitro release and biological activity of a drug (curcumin) loaded in BNNTs. Cells treated with curcumin-loaded BNNTs and stimulated with lipopolysaccharide were assessed for nitric oxide release and stimulation of IL-6 and TNF-α. The cellular trafficking of two cell-permeant dyes and a non-cell-permeant dye loaded within BNNTs was imaged. BNNTs loaded with up to 13 wt% fluorophores were internalized by cells and controlled release of curcumin triggered cellular pathways associated with the known anti-inflammatory effects of the drug. The overall findings indicate that BNNTs can function as nanocarriers of biologically relevant probes/drugs allowing one to examine/control their local intracellular localization and biochemical effects, leading the way to applications as intracellular nanosensors.

Geminiviruses and Plant Hosts: A Closer Examination of the Molecular Arms Race

PubMed Central

Ramesh, Shunmugiah V.; Sahu, Pranav P.; Prasad, Manoj; Praveen, Shelly; Pappu, Hanu R.

2017-01-01

Geminiviruses are plant-infecting viruses characterized by a single-stranded DNA (ssDNA) genome. Geminivirus-derived proteins are multifunctional and effective regulators in modulating the host cellular processes resulting in successful infection. Virus-host interactions result in changes in host gene expression patterns, reprogram plant signaling controls, disrupt central cellular metabolic pathways, impair plant’s defense system, and effectively evade RNA silencing response leading to host susceptibility. This review summarizes what is known about the cellular processes in the continuing tug of war between geminiviruses and their plant hosts at the molecular level. In addition, implications for engineered resistance to geminivirus infection in the context of a greater understanding of the molecular processes are also discussed. Finally, the prospect of employing geminivirus-based vectors in plant genome engineering and the emergence of powerful genome editing tools to confer geminivirus resistance are highlighted to complete the perspective on geminivirus-plant molecular interactions. PMID:28914771

Species as Stressors: Heterospecific Interactions and the Cellular Stress Response under Global Change.

PubMed

Gunderson, Alex R; King, Emily E; Boyer, Kirsten; Tsukimura, Brian; Stillman, Jonathon H

2017-07-01

Anthropogenic global change is predicted to increase the physiological stress of organisms through changes in abiotic conditions such as temperature, pH, and pollution. However, organisms can also experience physiological stress through interactions with other species, especially parasites, predators, and competitors. The stress of species interactions could be an important driver of species' responses to global change as the composition of biological communities change through factors such as distributional and phenological shifts. Interactions between biotic and abiotic stressors could also induce non-linear physiological stress responses under global change. One of the primary means by which organisms deal with physiological stress is through the cellular stress response (CSR), which is broadly the upregulation of a conserved set of genes that facilitate the removal and repair of damaged macromolecules. Here, we present data on behavioral interactions and CSR gene expression for two competing species of intertidal zone porcelain crab (Petrolisthes cinctipes and Petrolisthes manimaculis). We found that P. cinctipes and P. manimaculis engage in more agonistic behaviors when interacting with heterospecifics than conspecifics; however, we found no evidence that heterospecific interactions induced a CSR in these species. In addition to our new data, we review the literature with respect to CSR induction via species interactions, focusing on predator-prey systems and heterospecific competition. We find extensive evidence for predators to induce cellular stress and aspects of the CSR in prey, even in the absence of direct physical contact between species. Effects of heterospecific competition on the CSR have been studied far less, but we do find evidence that agonistic interactions with heterospecifics can induce components of the CSR. Across all published studies, there is clear evidence that species interactions can lead to cellular stress and induction of the CSR. Nonetheless, our understanding of species-induced cellular stress lags far behind our understanding of abiotic cellular stress. © The Author 2017. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Possible immunosuppressive effects of drug exposure and environmental and nutritional effects on infection and vaccination.

PubMed

Huemer, H P

2015-01-01

A variety of drugs which are not primarily considered to be immunosuppressive agents have been described to modulate the humoral and cellular immune response in humans or animals. Thereby they may have an influence on the effectiveness and possible side effects of vaccines. This mini review lists some of the different substance classes and also some of endogeneous, infectious, nutritional, and environmental influences with suspected capability to interfere with immunizations. Studies in most cases focused on substances with known immunosuppressive functions, but there is growing evidence for immunomodulatory effects also of commonly used drugs with wide distribution. In particular combinations of those antiproliferative and antiphlogistic side effects of different substance classes have not been studied in detail but may substantially interfere with the development of a functional humoral and cellular immune response. The drugs of importance include antipyretics, anticoagulants, tranquilizers, and substances influencing lipid metabolism but also commonly used drugs of abuse like alcohol or cannabinoids. Additional substances of environmental, nutritional, or microbiological origin may also play a role but their combinatory/synergistic effects have been disregarded so far due to the lack of systematic data and the complex study designs necessary to elucidate those complex epidemiologic questions.

Boosting BCG-primed responses with a subunit Apa vaccine during the waning phase improves immunity and imparts protection against Mycobacterium tuberculosis

PubMed Central

Nandakumar, Subhadra; Kannanganat, Sunil; Dobos, Karen M.; Lucas, Megan; Spencer, John S.; Amara, Rama Rao; Plikaytis, Bonnie B.; Posey, James E.; Sable, Suraj B.

2016-01-01

Heterologous prime–boosting has emerged as a powerful vaccination approach against tuberculosis. However, optimal timing to boost BCG-immunity using subunit vaccines remains unclear in clinical trials. Here, we followed the adhesin Apa-specific T-cell responses in BCG-primed mice and investigated its BCG-booster potential. The Apa-specific T-cell response peaked 32–52 weeks after parenteral or mucosal BCG-priming but waned significantly by 78 weeks. A subunit-Apa-boost during the contraction-phase of BCG-response had a greater effect on the magnitude and functional quality of specific cellular and humoral responses compared to a boost at the peak of BCG-response. The cellular response increased following mucosal BCG-prime–Apa-subunit-boost strategy compared to Apa-subunit-prime–BCG-boost approach. However, parenteral BCG-prime–Apa-subunit-boost by a homologous route was the most effective strategy in-terms of enhancing specific T-cell responses during waning in the lung and spleen. Two Apa-boosters markedly improved waning BCG-immunity and significantly reduced Mycobacterium tuberculosis burdens post-challenge. Our results highlight the challenges of optimization of prime–boost regimens in mice where BCG drives persistent immune-activation and suggest that boosting with a heterologous vaccine may be ideal once the specific persisting effector responses are contracted. Our results have important implications for design of prime–boost regimens against tuberculosis in humans. PMID:27173443

The effect of agglomeration state of silver and titanium dioxide nanoparticles on cellular response of HepG2, A549 and THP-1 cells.

PubMed

Lankoff, Anna; Sandberg, Wiggo J; Wegierek-Ciuk, Aneta; Lisowska, Halina; Refsnes, Magne; Sartowska, Bożena; Schwarze, Per E; Meczynska-Wielgosz, Sylwia; Wojewodzka, Maria; Kruszewski, Marcin

2012-02-05

Nanoparticles (NPs) occurring in the environment rapidly agglomerate and form particles of larger diameters. The extent to which this abates the effects of NPs has not been clarified. The motivation of this study was to examine how the agglomeration/aggregation state of silver (20nm and 200nm) and titanium dioxide (21nm) nanoparticles may affect the kinetics of cellular binding/uptake and ability to induce cytotoxic responses in THP1, HepG2 and A549 cells. Cellular binding/uptake, metabolic activation and cell death were assessed by the SSC flow cytometry measurements, the MTT-test and the propidium iodide assay. The three types of particles were efficiently taken up by the cells, decreasing metabolic activation and increasing cell death in all the cell lines. The magnitude of the studied endpoints depended on the agglomeration/aggregation state of particles, their size, time-point and cell type. Among the three cell lines tested, A549 cells were the most sensitive to these particles in relation to cellular binding/uptake. HepG2 cells showed a tendency to be more sensitive in relation to metabolic activation. THP-1 cells were the most resistant to all three types of particles in relation to all endpoints tested. Our findings suggest that particle features such as size and agglomeration status as well as the type of cells may contribute to nanoparticles biological impact. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Molecular and cellular mechanisms responsible for cellular stress and low-grade inflammation induced by a super-low dose of endotoxin.

PubMed

Baker, Bianca; Maitra, Urmila; Geng, Shuo; Li, Liwu

2014-06-06

Super-low-dose endotoxemia in experimental animals and humans is linked to low-grade chronic inflammatory diseases. However, the underlying molecular and cellular mechanisms are not well understood. In this study, we examined the effects of a super-low dose of LPS on low-grade inflammation in macrophages as well as underlying mechanisms. We observed that a super-low dose of LPS induces mitochondrial fission and cell necroptosis in primary murine macrophages, dependent upon interleukin 1 receptor-associated kinase (IRAK-1). Mechanistically, our study reveals that a super-low dose of LPS causes protein ubiquitination and degradation of mitofusin 1 (Mfn1), a molecule required for maintaining proper mitochondrial fusion. A super-low dose of LPS also leads to dephosphorylation and activation of Drp1, a molecule responsible for mitochondrial fission and cell necroptosis. Furthermore, we demonstrated that a super-low dose of LPS activates receptor interacting protein 3 kinase (RIP3), a key molecule critical for the assembly of the necrosome complex, the initiation of Drp1 dephosphorylation, and necroptosis. The effects of a super-low dose of LPS are abolished in macrophages harvested from IRAK-1-deficient mice. Taken together, our study identified a novel molecular pathway that leads to cellular stress and necroptosis in macrophages challenged with a super-low dose of endotoxin. This may reconcile low-grade inflammation often associated with low-grade endotoxemia. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Linking physiological and cellular responses to thermal stress: β-adrenergic blockade reduces the heat shock response in fish.

PubMed

Templeman, Nicole M; LeBlanc, Sacha; Perry, Steve F; Currie, Suzanne

2014-08-01

When faced with stress, animals use physiological and cellular strategies to preserve homeostasis. We were interested in how these high-level stress responses are integrated at the level of the whole animal. Here, we investigated the capacity of the physiological stress response, and specifically the β-adrenergic response, to affect the induction of the cellular heat shock proteins, HSPs, following a thermal stress in vivo. We predicted that blocking β-adrenergic stimulation during an acute heat stress in the whole animal would result in reduced levels of HSPs in red blood cells (RBCs) of rainbow trout compared to animals where adrenergic signaling remained intact. We first determined that a 1 h heat shock at 25 °C in trout acclimated to 13 °C resulted in RBC adrenergic stimulation as determined by a significant increase in cell swelling, a hallmark of the β-adrenergic response. A whole animal injection with the β2-adrenergic antagonist, ICI-118,551, successfully reduced this heat-induced RBC swelling. The acute heat shock caused a significant induction of HSP70 in RBCs of 13 °C-acclimated trout as well as a significant increase in plasma catecholamines. When heat-shocked fish were treated with ICI-118,551, we observed a significant attenuation of the HSP70 response. We conclude that circulating catecholamines influence the cellular heat shock response in rainbow trout RBCs, demonstrating physiological/hormonal control of the cellular stress response.

Calcium ion as intracellular messenger and cellular toxin.

PubMed

Rasmussen, H; Barrett, P; Smallwood, J; Bollag, W; Isales, C

1990-03-01

Ca2+ serves a nearly universal intracellular messenger function in cell activation, but excess Ca2+ is also a cellular toxin. The possibility of Ca2+ intoxication is minimized by an elaborate autoregulatory system in which changes in Ca2+ influx rate across the plasma membrane are rapidly compensated for by parallel changes in Ca2+ efflux rate. By this mean, cellular Ca2+ homestasis is maintained so that minimal changes in total cell calcium and cytosolic Ca2+ concentration occur during sustained Ca2(+)-mediated responses. Rather than a sustained increase in cytosolic Ca2+ concentration, it is the localized cycling of Ca2+ across the plasma membrane that is the critically important Ca2+ messenger during the sustained phase of cellular responses mediated via surface receptors linked to the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2). PIP2 hydrolysis gives rise to inositol(1,4,5)trisphosphate (IP3) and diacylglycerol (DAG). The IP3 acts to release Ca2+ from an intracellular pool, thereby causing a transient rise in cytosolic Ca2+ concentration. This transient Ca2+ signal activates calmodulin-dependent protein kinases transiently, and hence, causes the transient phosphorylation of a subset of cellular proteins that mediate the initial phase of the response. The DAG brings about the association of protein kinase C (PKC) with the plasma membrane where a receptor-mediated increase in Ca2+ cycling across the membrane regulates PKC activity. The sustained phosphorylation of a second subset of proteins by PKC mediates the sustained phase of the response. Hence, Ca2+ serves as a messenger during both phases of the cellular response, but its cellular sites of action, its mechanisms of generation, and its molecular targets differ during the initial and sustained phases of the response.(ABSTRACT TRUNCATED AT 250 WORDS)

Calcium ion as intracellular messenger and cellular toxin.

PubMed Central

Rasmussen, H; Barrett, P; Smallwood, J; Bollag, W; Isales, C

1990-01-01

Ca2+ serves a nearly universal intracellular messenger function in cell activation, but excess Ca2+ is also a cellular toxin. The possibility of Ca2+ intoxication is minimized by an elaborate autoregulatory system in which changes in Ca2+ influx rate across the plasma membrane are rapidly compensated for by parallel changes in Ca2+ efflux rate. By this mean, cellular Ca2+ homestasis is maintained so that minimal changes in total cell calcium and cytosolic Ca2+ concentration occur during sustained Ca2(+)-mediated responses. Rather than a sustained increase in cytosolic Ca2+ concentration, it is the localized cycling of Ca2+ across the plasma membrane that is the critically important Ca2+ messenger during the sustained phase of cellular responses mediated via surface receptors linked to the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2). PIP2 hydrolysis gives rise to inositol(1,4,5)trisphosphate (IP3) and diacylglycerol (DAG). The IP3 acts to release Ca2+ from an intracellular pool, thereby causing a transient rise in cytosolic Ca2+ concentration. This transient Ca2+ signal activates calmodulin-dependent protein kinases transiently, and hence, causes the transient phosphorylation of a subset of cellular proteins that mediate the initial phase of the response. The DAG brings about the association of protein kinase C (PKC) with the plasma membrane where a receptor-mediated increase in Ca2+ cycling across the membrane regulates PKC activity. The sustained phosphorylation of a second subset of proteins by PKC mediates the sustained phase of the response. Hence, Ca2+ serves as a messenger during both phases of the cellular response, but its cellular sites of action, its mechanisms of generation, and its molecular targets differ during the initial and sustained phases of the response.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2190811

Inhibition of the Nedd8 system sensitizes cells to DNA Inter-strand crosslinking agents

PubMed Central

Kee, Younghoon; Huang, Min; Chang, Sophia; Moreau, Lisa A.; Park, Eunmi; Smith, Peter G.; D’Andrea, Alan D.

2012-01-01

The Fanconi Anemia (FA) pathway is required for repair of DNA interstrand crosslinks (ICLs). FA pathway-deficient cells are hypersensitive to DNA ICL-inducing drugs such as Cisplatin. Conversely, hyperactivation of the FA pathway is a mechanism that may underlie cellular resistance to DNA ICL agents. Modulating FANCD2 monoubiquitination, a key step in the FA pathway, may be an effective therapeutic approach to conferring cellular sensitivity to ICL agents. Here, we show that inhibition of the Nedd8 conjugation system increases cellular sensitivity to DNA ICL-inducing agents. Mechanistically, the Nedd8 inhibition, either by siRNA-mediated knockdown of Nedd8 conjugating enzymes or treatment with a Nedd8 activating enzyme inhibitor MLN4924, suppressed DNA damage-induced FANCD2 monoubiquitination and CHK1 phosphorylation. Our data indicate that inhibition of the FA pathway is largely responsible for the heightened cellular sensitivity to DNA ICLs upon Nedd8 inhibition. These results suggest that a combination of Nedd8 inhibition with ICL-inducing agents may be an effective strategy for sensitizing a subset of drug-resistant cancer cells. PMID:22219386

Simulated microgravity induces an inflammatory response in the common carotid artery of rats.

PubMed

Liu, Huan; Wang, Zhong-Chao; Yue, Yuan; Yu, Jin-Wen; Cai, Yue; Bai, Yun-Gang; Zhang, Hai-Jun; Bao, Jun-Xiang; Ren, Xin-Ling; Xie, Man-Jiang; Ma, Jin

2014-08-01

Post-spaceflight orthostatic intolerance is one of the most important adverse effects after exposure to space microgravity, and there are still no effective countermeasures. It has been considered that arterial remodeling may play an important role in the occurrence of post-spaceflight orthostatic intolerance, but the cellular mechanisms remain unknown. In this study, we investigated whether an inflammatory response exists in the common carotid artery of rats exposed to simulated microgravity. For this, Sprague-Dawley rats were subjected to 4 weeks of hindlimb unweighting to simulate microgravity. The expression levels of the adhesion molecules E-selectin and vascular cell adhesion molecule-1 (VCAM-1), and the cytokine monocyte chemoattractant protein-1 (MCP-1) in the common carotid artery of simulated microgravity rats were evaluated by immunohistochemical staining, quantitative RT-PCR, and Western blot analyses. The recruitment of monocytes in the common carotid artery of rats exposed to simulated microgravity was investigated by en face immunofluorescence staining and monocyte binding assays. Our results provided convincing evidence that there is an inflammatory response in the common carotid artery of rats exposed to simulated microgravity. Our work suggests that the inflammatory response may be a novel cellular mechanism that is responsible for the arterial remodeling that occurs during exposure to microgravity.

Bacterial RNA induces myocyte cellular dysfunction through the activation of PKR

PubMed Central

Bleiblo, Farag; Michael, Paul; Brabant, Danielle; Ramana, Chilakamarti V.; Tai, TC; Saleh, Mazen; Parrillo, Joseph E.; Kumar, Anand

2012-01-01

Severe sepsis and the ensuing septic shock are serious life threatening conditions. These diseases are triggered by the host's over exuberant systemic response to the infecting pathogen. Several surveillance mechanisms have evolved to discriminate self from foreign RNA and accordingly trigger effective cellular responses to target the pathogenic threats. The RNA-dependent protein kinase (PKR) is a key component of the cytoplasmic RNA sensors involved in the recognition of viral double-stranded RNA (dsRNA). Here, we identify bacterial RNA as a distinct pathogenic pattern recognized by PKR. Our results indicate that natural RNA derived from bacteria directly binds to and activates PKR. We further show that bacterial RNA induces human cardiac myocyte apoptosis and identify the requirement for PKR in mediating this response. In addition to bacterial immunity, the results presented here may also have implications in cardiac pathophysiology. PMID:22833816

Role of Integrin in Mechanical Loading of Osteoblasts

NASA Technical Reports Server (NTRS)

Globus, Ruth; Demsky, Caroline

2000-01-01

Mechanical forces generated by gravity, weightbearing, and muscle contraction play a key role in the genesis and maintenance of skeletal structure. The molecular mechanisms that mediate changes in osteoblast activity in response to altered patterns of skeletal loading are not known, and a better understanding of these processes may be essential for developing effective treatment strategies to prevent disuse osteoporosis. We have elucidated specific integrin/ECM (extracellular matrix) interactions that are required for osteoblast differentiation and survival and have developed a useful loading system to further explore the molecular basis of mechano-sensitivity of osteoblasts. The long term goal of our collaborative research is to understand how the ECM and cell adhesion proteins and integrins interaction to mediate the response of osteoblasts and their progenitors to mechanical loading. We suggest that integrin/ECM interactions are crucial for basic cellular processes, including differentiation and survival, as well as to participate in detecting and mediating cellular responses to mechanical stimuli.

Soft x rays as a tool to investigate radiation-sensitive sites in mammalian cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brenner, D.J.; Zaider, M.

1983-01-01

It is now clear that the initial geometrical distribution of primary radiation products in irradiated biological matter is fundamental to the observed end point (cell killing, mutation induction, chromosome aberrations, etc.). In recent years much evidence has accumulated indicating that for all radiations, physical quantities averaged over cellular dimensions (micrometers) are not good predictors of biological effect, and that energy-deposition processes at the nanometer level are critical. Thus irradiation of cells with soft x rays whose secondary electrons have ranges of the order of nanometers is a unique tool for investigating different models for predicting the biological effects of radiation.more » We demonstrate techniques whereby the biological response of the cell and the physical details of the energy deposition processes may be separated or factorized, so that given the response of a cellular system to, say, soft x rays, the response of the cell to any other radiation may be predicted. The special advantages of soft x rays for eliciting this information and also information concerning the geometry of the radiation sensitive structures within the cell are discussed.« less

Toxic Diatom Aldehydes Affect Defence Gene Networks in Sea Urchins

PubMed Central

Varrella, Stefano; Ruocco, Nadia; Ianora, Adrianna; Bentley, Matt G.; Costantini, Maria

2016-01-01

Marine organisms possess a series of cellular strategies to counteract the negative effects of toxic compounds, including the massive reorganization of gene expression networks. Here we report the modulated dose-dependent response of activated genes by diatom polyunsaturated aldehydes (PUAs) in the sea urchin Paracentrotus lividus. PUAs are secondary metabolites deriving from the oxidation of fatty acids, inducing deleterious effects on the reproduction and development of planktonic and benthic organisms that feed on these unicellular algae and with anti-cancer activity. Our previous results showed that PUAs target several genes, implicated in different functional processes in this sea urchin. Using interactomic Ingenuity Pathway Analysis we now show that the genes targeted by PUAs are correlated with four HUB genes, NF-κB, p53, δ-2-catenin and HIF1A, which have not been previously reported for P. lividus. We propose a working model describing hypothetical pathways potentially involved in toxic aldehyde stress response in sea urchins. This represents the first report on gene networks affected by PUAs, opening new perspectives in understanding the cellular mechanisms underlying the response of benthic organisms to diatom exposure. PMID:26914213

Effects of scaffold architecture on mechanical characteristics and osteoblast response to static and perfusion bioreactor cultures.

PubMed

Bartnikowski, Michal; Klein, Travis J; Melchels, Ferry P W; Woodruff, Maria A

2014-07-01

Tissue engineering focuses on the repair and regeneration of tissues through the use of biodegradable scaffold systems that structurally support regions of injury while recruiting and/or stimulating cell populations to rebuild the target tissue. Within bone tissue engineering, the effects of scaffold architecture on cellular response have not been conclusively characterized in a controlled-density environment. We present a theoretical and practical assessment of the effects of polycaprolactone (PCL) scaffold architectural modifications on mechanical and flow characteristics as well as MC3T3-E1 preosteoblast cellular response in an in vitro static plate and custom-designed perfusion bioreactor model. Four scaffold architectures were contrasted, which varied in inter-layer lay-down angle and offset between layers, while maintaining a structural porosity of 60 ± 5%. We established that as layer angle was decreased (90° vs. 60°) and offset was introduced (0 vs. 0.5 between layers), structural stiffness, yield stress, strength, pore size, and permeability decreased, while computational fluid dynamics-modeled wall shear stress was increased. Most significant effects were noted with layer offset. Seeding efficiencies in static culture were also dramatically increased due to offset (∼ 45% to ∼ 86%), with static culture exhibiting a much higher seeding efficiency than perfusion culture. Scaffold architecture had minimal effect on cell response in static culture. However, architecture influenced osteogenic differentiation in perfusion culture, likely by modifying the microfluidic environment. © 2014 Wiley Periodicals, Inc.

Ionizing radiation-induced metabolic oxidative stress and prolonged cell injury

PubMed Central

Azzam, Edouard I.; Jay-Gerin, Jean-Paul; Pain, Debkumar

2013-01-01

Cellular exposure to ionizing radiation leads to oxidizing events that alter atomic structure through direct interactions of radiation with target macromolecules or via products of water radiolysis. Further, the oxidative damage may spread from the targeted to neighboring, non-targeted bystander cells through redox-modulated intercellular communication mechanisms. To cope with the induced stress and the changes in the redox environment, organisms elicit transient responses at the molecular, cellular and tissue levels to counteract toxic effects of radiation. Metabolic pathways are induced during and shortly after the exposure. Depending on radiation dose, dose-rate and quality, these protective mechanisms may or may not be sufficient to cope with the stress. When the harmful effects exceed those of homeostatic biochemical processes, induced biological changes persist and may be propagated to progeny cells. Physiological levels of reactive oxygen and nitrogen species play critical roles in many cellular functions. In irradiated cells, levels of these reactive species may be increased due to perturbations in oxidative metabolism and chronic inflammatory responses, thereby contributing to the long-term effects of exposure to ionizing radiation on genomic stability. Here, in addition to immediate biological effects of water radiolysis on DNA damage, we also discuss the role of mitochondria in the delayed outcomes of ionization radiation. Defects in mitochondrial functions lead to accelerated aging and numerous pathological conditions. Different types of radiation vary in their linear energy transfer (LET) properties, and we discuss their effects on various aspects of mitochondrial physiology. These include short and long-term in vitro and in vivo effects on mitochondrial DNA, mitochondrial protein import and metabolic and antioxidant enzymes. PMID:22182453

Interaction of carbon nanohorns with plants: Uptake and biological effects

DOE PAGES

Lahiani, Mohamed H.; Chen, Jihua; Irin, Fahmida; ...

2014-10-07

Single-Walled Carbon Nanohorns (SWCNHs) are a unique carbon-based nanomaterial with promising application in different fields including, medicine, genetic engineering and horticulture. Here, we investigated the biological response of six crop species (barley, corn, rice, soybean, switchgrass, tomato) and tobacco cell culture to the exposure of SWCNHs. We found that SWCNHs can activate seed germination of selected crops and enhance growth of different organs of corn, tomato, rice and soybean. At cellular level, growth of tobacco cells was increased in response to exposure of SWCNHs (78% increase compared to control). Uptake of SWCNHs by exposed crops and tobacco cells was confirmedmore » by transmission electron microscopy (TEM) and quantified by microwave induced heating (MIH) technique. At genetic level, SWCNHs were able to affect expression of a number of tomato genes that are involved in stress responses, cellular responses and metabolic processes. Our conclusion is that SWCNHs can be used as plant growth regulators and have the potential for plant-related applications.« less

Atg5- and Atg7-dependent autophagy in dopaminergic neurons regulates cellular and behavioral responses to morphine.

PubMed

Su, Ling-Yan; Luo, Rongcan; Liu, Qianjin; Su, Jing-Ran; Yang, Lu-Xiu; Ding, Yu-Qiang; Xu, Lin; Yao, Yong-Gang

2017-09-02

The molecular basis of chronic morphine exposure remains unknown. In this study, we hypothesized that macroautophagy/autophagy of dopaminergic neurons would mediate the alterations of neuronal dendritic morphology and behavioral responses induced by morphine. Chronic morphine exposure caused Atg5 (autophagy-related 5)- and Atg7 (autophagy-related 7)-dependent and dopaminergic neuron-specific autophagy resulting in decreased neuron dendritic spines and the onset of addictive behaviors. In cultured primary midbrain neurons, morphine treatment significantly reduced total dendritic length and complexity, and this effect could be reversed by knockdown of Atg5 or Atg7. Mice deficient for Atg5 or Atg7 specifically in the dopaminergic neurons were less sensitive to developing a morphine reward response, behavioral sensitization, analgesic tolerance and physical dependence compared to wild-type mice. Taken together, our findings suggested that the Atg5- and Atg7-dependent autophagy of dopaminergic neurons contributed to cellular and behavioral responses to morphine and may have implications for the future treatment of drug addiction.

pH-Responsive Micelle-Based Cytoplasmic Delivery System for Induction of Cellular Immunity.

PubMed

Yuba, Eiji; Sakaguchi, Naoki; Kanda, Yuhei; Miyazaki, Maiko; Koiwai, Kazunori

2017-11-04

(1) Background: Cytoplasmic delivery of antigens is crucial for the induction of cellular immunity, which is an important immune response for the treatment of cancer and infectious diseases. To date, fusogenic protein-incorporated liposomes and pH-responsive polymer-modified liposomes have been used to achieve cytoplasmic delivery of antigen via membrane rupture or fusion with endosomes. However, a more versatile cytoplasmic delivery system is desired for practical use. For this study, we developed pH-responsive micelles composed of dilauroyl phosphatidylcholine (DLPC) and deoxycholic acid and investigated their cytoplasmic delivery performance and immunity-inducing capability. (2) Methods: Interaction of micelles with fluorescence dye-loaded liposomes, intracellular distribution of micelles, and antigenic proteins were observed. Finally, antigen-specific cellular immune response was evaluated in vivo using ELIspot assay. (3) Results: Micelles induced leakage of contents from liposomes via lipid mixing at low pH. Micelles were taken up by dendritic cells mainly via macropinocytosis and delivered ovalbumin (OVA) into the cytosol. After intradermal injection of micelles and OVA, OVA-specific cellular immunity was induced in the spleen. (4) Conclusions: pH-responsive micelles composed of DLPC and deoxycholic acid are promising as enhancers of cytosol delivery of antigens and the induction capability of cellular immunity for the treatment of cancer immunotherapy and infectious diseases.

Interleukin-7 in Patients With Chronic Hepatitis B May Have Effect on T Follicular Helper Cells and Specific Cellular Immunity.

PubMed

Zhong, Hua; Xibing, Gu; Yaping, Dai; Zheng, Wang; Decai, Fu; Xiaoye, Guo; Hangyuan, Wu; Dong, Wang; Zhonghua, Lu

2016-09-01

In patients with chronic hepatitis B (CHB), the relation of interkeukin-7 (IL-7) to either the T follicular helper cells (Tfh cells) or to a specific cellular immune response is not clear. The present study aims to explore the possible relationship of IL-7 to Tfh cells and to hepatitis B virus (HBV)-specific cellular immune response in patients with CHB. Ninety-one adult patients with CHB were divided into groups A, B, and C, according to the patients' IL-7 levels (low, medium, and high). Tfh cells and HBV-specific cytotoxic T lymphocytes (CTLs) were detected with flow cytometry; IL-7 and IL-21 were determined with a double antibody sandwich enzyme-linked immunosorbent assay; and HBV DNA was determined by using a real-time fluorescent quantitative polymerase chain reaction. The results showed that the levels of IL-7, Tfh cells, IL-21, and HBV-specific CTLs of patients in group C were significantly higher than those of patients in group B, (P < 0.01 for each comparison) and that the levels of these four parameters of patients in group B were significantly higher than those of the patients in group A (P < 0.01 for each comparison). Meanwhile, the level of HBV DNA of the patients in group C was significantly lower than that of the patients in group B (P < 0.01), and that of the patients in group B was significantly lower than that of the patients in group A (P < 0.05). Multiple linear regression analyses showed that IL-7, Tfh cells, IL-21, and HBV-specific CTL might have effects on HBV DNA and that only the HBV-specific CTL had an independent effect on HBV DNA (P < 0.01). IL-7, Tfh cells, and IL-21 showed independent effects on HBV-specific CTL (P < 0.05, P < 0.01, and P < 0.01). This study suggests that the IL-7 level of CHB patients may be related to Tfh cells. In CHB patients, IL-7 possibly increases the level of Tfh cells and HBV-specific cellular immune responses and thereby reduces the HBV DNA level.

Proteomic analysis of the response of α-ketoglutarate-producer Yarrowia lipolytica WSH-Z06 to environmental pH stimuli.

PubMed

Guo, Hongwei; Wan, Hui; Chen, Hongwen; Fang, Fang; Liu, Song; Zhou, Jingwen

2016-10-01

During bioproduction of short-chain carboxylates, a shift in pH is a common strategy for enhancing the biosynthesis of target products. Based on two-dimensional gel electrophoresis, comparative proteomics analysis of general and mitochondrial protein samples was used to investigate the cellular responses to environmental pH stimuli in the α-ketoglutarate overproducer Yarrowia lipolytica WSH-Z06. The lower environmental pH stimuli tensioned intracellular acidification and increased the level of reactive oxygen species (ROS). A total of 54 differentially expressed protein spots were detected, and 11 main cellular processes were identified to be involved in the cellular response to environmental pH stimuli. Slight decrease in cytoplasmic pH enhanced the cellular acidogenicity by elevating expression level of key enzymes in tricarboxylic acid cycle (TCA cycle). Enhanced energy biosynthesis, ROS elimination, and membrane potential homeostasis processes were also employed as cellular defense strategies to compete with environmental pH stimuli. Owing to its antioxidant role of α-ketoglutarate, metabolic flux shifted to α-ketoglutarate under lower pH by Y. lipolytica in response to acidic pH stimuli. The identified differentially expressed proteins provide clues for understanding the mechanisms of the cellular responses and for enhancing short-chain carboxylate production through metabolic engineering or process optimization strategies in combination with manipulation of environmental conditions.

Bridging the gap between high-throughput genetic and transcriptional data reveals cellular pathways responding to alpha-synuclein toxicity

PubMed Central

Yeger-Lotem, Esti; Riva, Laura; Su, Linhui Julie; Gitler, Aaron D.; Cashikar, Anil; King, Oliver D.; Auluck, Pavan K.; Geddie, Melissa L.; Valastyan, Julie S.; Karger, David R.; Lindquist, Susan; Fraenkel, Ernest

2009-01-01

Cells respond to stimuli by changes in various processes, including signaling pathways and gene expression. Efforts to identify components of these responses increasingly depend on mRNA profiling and genetic library screens, yet the functional roles of the genes identified by these assays often remain enigmatic. By comparing the results of these two assays across various cellular responses, we found that they are consistently distinct. Moreover, genetic screens tend to identify response regulators, while mRNA profiling frequently detects metabolic responses. We developed an integrative approach that bridges the gap between these data using known molecular interactions, thus highlighting major response pathways. We harnessed this approach to reveal cellular pathways related to alpha-synuclein, a small lipid-binding protein implicated in several neurodegenerative disorders including Parkinson disease. For this we screened an established yeast model for alpha-synuclein toxicity to identify genes that when overexpressed alter cellular survival. Application of our algorithm to these data and data from mRNA profiling provided functional explanations for many of these genes and revealed novel relations between alpha-synuclein toxicity and basic cellular pathways. PMID:19234470

Anti-oxidative cellular protection effect of fasting-induced autophagy as a mechanism for hormesis.

PubMed

Moore, Michael N; Shaw, Jennifer P; Ferrar Adams, Dawn R; Viarengo, Aldo

2015-06-01

The aim of this investigation was to test the hypothesis that fasting-induced augmented lysosomal autophagic turnover of cellular proteins and organelles will reduce potentially harmful lipofuscin (age-pigment) formation in cells by more effectively removing oxidatively damaged proteins. An animal model (marine snail--common periwinkle, Littorina littorea) was used to experimentally test this hypothesis. Snails were deprived of algal food for 7 days to induce an augmented autophagic response in their hepatopancreatic digestive cells (hepatocyte analogues). This treatment resulted in a 25% reduction in the cellular content of lipofuscin in the digestive cells of the fasting animals in comparison with snails fed ad libitum on green alga (Ulva lactuca). Similar findings have previously been observed in the digestive cells of marine mussels subjected to copper-induced oxidative stress. Additional measurements showed that fasting significantly increased cellular health based on lysosomal membrane stability, and reduced lipid peroxidation and lysosomal/cellular triglyceride. These findings support the hypothesis that fasting-induced augmented autophagic turnover of cellular proteins has an anti-oxidative cytoprotective effect by more effectively removing damaged proteins, resulting in a reduction in the formation of potentially harmful proteinaceous aggregates such as lipofuscin. The inference from this study is that autophagy is important in mediating hormesis. An increase was demonstrated in physiological complexity with fasting, using graph theory in a directed cell physiology network (digraph) model to integrate the various biomarkers. This was commensurate with increased health status, and supportive of the hormesis hypothesis. The potential role of enhanced autophagic lysosomal removal of damaged proteins in the evolutionary acquisition of stress tolerance in intertidal molluscs is discussed and parallels are drawn with the growing evidence for the involvement of autophagy in hormesis and anti-ageing processes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Creatine Protects against Excitoxicity in an In Vitro Model of Neurodegeneration

PubMed Central

Genius, Just; Geiger, Johanna; Bender, Andreas; Möller, Hans-Jürgen; Klopstock, Thomas; Rujescu, Dan

2012-01-01

Creatine has been shown to be neuroprotective in aging, neurodegenerative conditions and brain injury. As a common molecular background, oxidative stress and disturbed cellular energy homeostasis are key aspects in these conditions. Moreover, in a recent report we could demonstrate a life-enhancing and health-promoting potential of creatine in rodents, mainly due to its neuroprotective action. In order to investigate the underlying pharmacology mediating these mainly neuroprotective properties of creatine, cultured primary embryonal hippocampal and cortical cells were challenged with glutamate or H2O2. In good agreement with our in vivo data, creatine mediated a direct effect on the bioenergetic balance, leading to an enhanced cellular energy charge, thereby acting as a neuroprotectant. Moreover, creatine effectively antagonized the H2O2-induced ATP depletion and the excitotoxic response towards glutamate, while not directly acting as an antioxidant. Additionally, creatine mediated a direct inhibitory action on the NMDA receptor-mediated calcium response, which initiates the excitotoxic cascade. Even excessive concentrations of creatine had no neurotoxic effects, so that high-dose creatine supplementation as a health-promoting agent in specific pathological situations or as a primary prophylactic compound in risk populations seems feasible. In conclusion, we were able to demonstrate that the protective potential of creatine was primarily mediated by its impact on cellular energy metabolism and NMDA receptor function, along with reduced glutamate spillover, oxidative stress and subsequent excitotoxicity. PMID:22347384

Deoxycholic acid modulates cell death signaling through changes in mitochondrial membrane properties[S

PubMed Central

Sousa, Tânia; Castro, Rui E.; Pinto, Sandra N.; Coutinho, Ana; Lucas, Susana D.; Moreira, Rui; Rodrigues, Cecília M. P.; Prieto, Manuel; Fernandes, Fábio

2015-01-01

Cytotoxic bile acids, such as deoxycholic acid (DCA), are responsible for hepatocyte cell death during intrahepatic cholestasis. The mechanisms responsible for this effect are unclear, and recent studies conflict, pointing to either a modulation of plasma membrane structure or mitochondrial-mediated toxicity through perturbation of mitochondrial outer membrane (MOM) properties. We conducted a comprehensive comparative study of the impact of cytotoxic and cytoprotective bile acids on the membrane structure of different cellular compartments. We show that DCA increases the plasma membrane fluidity of hepatocytes to a minor extent, and that this effect is not correlated with the incidence of apoptosis. Additionally, plasma membrane fluidity recovers to normal values over time suggesting the presence of cellular compensatory mechanisms for this perturbation. Colocalization experiments in living cells confirmed the presence of bile acids within mitochondrial membranes. Experiments with active isolated mitochondria revealed that physiologically active concentrations of DCA change MOM order in a concentration- and time-dependent manner, and that these changes preceded the mitochondrial permeability transition. Importantly, these effects are not observed on liposomes mimicking MOM lipid composition, suggesting that DCA apoptotic activity depends on features of mitochondrial membranes that are absent in protein-free mimetic liposomes, such as the double-membrane structure, lipid asymmetry, or mitochondrial protein environment. In contrast, the mechanism of action of cytoprotective bile acids is likely not associated with changes in cellular membrane structure. PMID:26351365

Cross-reactivity of anti-HIV-1 T cell immune responses among the major HIV-1 clades in HIV-1-positive individuals from 4 continents.

PubMed

Coplan, Paul M; Gupta, Swati B; Dubey, Sheri A; Pitisuttithum, Punnee; Nikas, Alex; Mbewe, Bernard; Vardas, Efthyia; Schechter, Mauro; Kallas, Esper G; Freed, Dan C; Fu, Tong-Ming; Mast, Christopher T; Puthavathana, Pilaipan; Kublin, James; Brown Collins, Kelly; Chisi, John; Pendame, Richard; Thaler, Scott J; Gray, Glenda; Mcintyre, James; Straus, Walter L; Condra, Jon H; Mehrotra, Devan V; Guess, Harry A; Emini, Emilio A; Shiver, John W

2005-05-01

The genetic diversity of human immunodeficiency virus type 1 (HIV-1) raises the question of whether vaccines that include a component to elicit antiviral T cell immunity based on a single viral genetic clade could provide cellular immune protection against divergent HIV-1 clades. Therefore, we quantified the cross-clade reactivity, among unvaccinated individuals, of anti-HIV-1 T cell responses to the infecting HIV-1 clade relative to other major circulating clades. Cellular immune responses to HIV-1 clades A, B, and C were compared by standardized interferon- gamma enzyme-linked immunospot assays among 250 unvaccinated individuals, infected with diverse HIV-1 clades, from Brazil, Malawi, South Africa, Thailand, and the United States. Cross-clade reactivity was evaluated by use of the ratio of responses to heterologous versus homologous (infecting) clades of HIV-1. Cellular immune responses were predominantly focused on viral Gag and Nef proteins. Cross-clade reactivity of cellular immune responses to HIV-1 clade A, B, and C proteins was substantial for Nef proteins (ratio, 0.97 [95% confidence interval, 0.89-1.05]) and lower for Gag proteins (ratio, 0.67 [95% confidence interval, 0.62-0.73]). The difference in cross-clade reactivity to Nef and Gag proteins was significant (P<.0001). Cross-clade reactivity of cellular immune responses can be substantial but varies by viral protein.

Hierarchical Targeting Strategy for Enhanced Tumor Tissue Accumulation/Retention and Cellular Internalization.

PubMed

Wang, Sheng; Huang, Peng; Chen, Xiaoyuan

2016-09-01

Targeted delivery of therapeutic agents is an important way to improve the therapeutic index and reduce side effects. To design nanoparticles for targeted delivery, both enhanced tumor tissue accumulation/retention and enhanced cellular internalization should be considered simultaneously. So far, there have been very few nanoparticles with immutable structures that can achieve this goal efficiently. Hierarchical targeting, a novel targeting strategy based on stimuli responsiveness, shows good potential to enhance both tumor tissue accumulation/retention and cellular internalization. Here, the recent design and development of hierarchical targeting nanoplatforms, based on changeable particle sizes, switchable surface charges and activatable surface ligands, will be introduced. In general, the targeting moieties in these nanoplatforms are not activated during blood circulation for efficient tumor tissue accumulation, but re-activated by certain internal or external stimuli in the tumor microenvironment for enhanced cellular internalization. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Mechanisms of Cellular Membrane Effects of TCDD, Selected Perfluorinated Acids and Polyhalogenated Aromatic Hydrocarbons

DTIC Science & Technology

1985-02-01

toxic response of both cell lines after treatment with the perfluorinated acids ( perfluoro -n-octanoic acid, 9-H hexadecafluoro-n-nonanoic acid, and...throughout the experiments to eliminate the effect of serum on toxicity. The results for perfluoro -n-octanoic acid ( PFOA ) in both cell lines are presented in...the TK+/+ cells but not in the TK+/- cells. The results for the perfluoro -n-decanoic acid ( PFDA ) are presented in Table 3. A dose-response reldtionship

WE-DE-202-02: Are Track Structure Simulations Truly Needed for Radiobiology at the Cellular and Tissue Levels?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stewart, R.

Radiation therapy for the treatment of cancer has been established as a highly precise and effective way to eradicate a localized region of diseased tissue. To achieve further significant gains in the therapeutic ratio, we need to move towards biologically optimized treatment planning. To achieve this goal, we need to understand how the radiation-type dependent patterns of induced energy depositions within the cell (physics) connect via molecular, cellular and tissue reactions to treatment outcome such as tumor control and undesirable effects on normal tissue. Several computational biology approaches have been developed connecting physics to biology. Monte Carlo simulations are themore » most accurate method to calculate physical dose distributions at the nanometer scale, however simulations at the DNA scale are slow and repair processes are generally not simulated. Alternative models that rely on the random formation of individual DNA lesions within one or two turns of the DNA have been shown to reproduce the clusters of DNA lesions, including single strand breaks (SSBs), double strand breaks (DSBs) without the need for detailed track structure simulations. Efficient computational simulations of initial DNA damage induction facilitate computational modeling of DNA repair and other molecular and cellular processes. Mechanistic, multiscale models provide a useful conceptual framework to test biological hypotheses and help connect fundamental information about track structure and dosimetry at the sub-cellular level to dose-response effects on larger scales. In this symposium we will learn about the current state of the art of computational approaches estimating radiation damage at the cellular and sub-cellular scale. How can understanding the physics interactions at the DNA level be used to predict biological outcome? We will discuss if and how such calculations are relevant to advance our understanding of radiation damage and its repair, or, if the underlying biological processes are too complex for a mechanistic approach. Can computer simulations be used to guide future biological research? We will debate the feasibility of explaining biology from a physicists’ perspective. Learning Objectives: Understand the potential applications and limitations of computational methods for dose-response modeling at the molecular, cellular and tissue levels Learn about mechanism of action underlying the induction, repair and biological processing of damage to DNA and other constituents Understand how effects and processes at one biological scale impact on biological processes and outcomes on other scales J. Schuemann, NCI/NIH grantsS. McMahon, Funding: European Commission FP7 (grant EC FP7 MC-IOF-623630)« less

Electrochemical Cathodic Polarization, a Simplified Method That Can Modified and Increase the Biological Activity of Titanium Surfaces: A Systematic Review

PubMed Central

2016-01-01

Background The cathodic polarization seems to be an electrochemical method capable of modifying and coat biomolecules on titanium surfaces, improving the surface activity and promoting better biological responses. Objective The aim of the systematic review is to assess the scientific literature to evaluate the cellular response produced by treatment of titanium surfaces by applying the cathodic polarization technique. Data, Sources, and Selection The literature search was performed in several databases including PubMed, Web of Science, Scopus, Science Direct, Scielo and EBSCO Host, until June 2016, with no limits used. Eligibility criteria were used and quality assessment was performed following slightly modified ARRIVE and SYRCLE guidelines for cellular studies and animal research. Results Thirteen studies accomplished the inclusion criteria and were considered in the review. The quality of reporting studies in animal models was low and for the in vitro studies it was high. The in vitro and in vivo results reported that the use of cathodic polarization promoted hydride surfaces, effective deposition, and adhesion of the coated biomolecules. In the experimental groups that used the electrochemical method, cellular viability, proliferation, adhesion, differentiation, or bone growth were better or comparable with the control groups. Conclusions The use of the cathodic polarization method to modify titanium surfaces seems to be an interesting method that could produce active layers and consequently enhance cellular response, in vitro and in vivo animal model studies. PMID:27441840

Epidermal Homeostasis and Radiation Responses in a Multiscale Tissue Modeling Framework

NASA Technical Reports Server (NTRS)

Hu, Shaowen; Cucinotta, Francis A.

2013-01-01

The surface of skin is lined with several thin layers of epithelial cells that are maintained throughout life time by a small population of stem cells. High dose radiation exposures could injure and deplete the underlying proliferative cells and induce cutaneous radiation syndrome. In this work we propose a multiscale computational model for skin epidermal dynamics that links phenomena occurring at the subcellular, cellular, and tissue levels of organization, to simulate the experimental data of the radiation response of swine epidermis, which is closely similar to human epidermis. Incorporating experimentally measured histological and cell kinetic parameters, we obtain results of population kinetics and proliferation indexes comparable to observations in unirradiated and acutely irradiated swine experiments. At the sub-cellular level, several recently published Wnt signaling controlled cell-cycle models are applied and the roles of key components and parameters are analyzed. Based on our simulation results, we demonstrate that a moderate increase of proliferation rate for the survival proliferative cells is sufficient to fully repopulate the area denuded by high dose radiation, as long as the integrity of underlying basement membrane is maintained. Our work highlights the importance of considering proliferation kinetics as well as the spatial organization of tissues when conducting in vivo investigations of radiation responses. This integrated model allow us to test the validity of several basic biological rules at the cellular level and sub-cellular mechanisms by qualitatively comparing simulation results with published research, and enhance our understanding of the pathophysiological effects of ionizing radiation on skin.

The catalytic A1 domains of cholera toxin and heat-labile enterotoxin are potent DNA adjuvants that evoke mixed Th1/Th17 cellular immune responses

PubMed Central

Bagley, Kenneth; Xu, Rong; Ota-Setlik, Ayuko; Egan, Michael; Schwartz, Jennifer; Fouts, Timothy

2015-01-01

DNA encoded adjuvants are well known for increasing the magnitude of cellular and/or humoral immune responses directed against vaccine antigens. DNA adjuvants can also tune immune responses directed against vaccine antigens to better protect against infection of the target organism. Two potent DNA adjuvants that have unique abilities to tune immune responses are the catalytic A1 domains of Cholera Toxin (CTA1) and Heat-Labile Enterotoxin (LTA1). Here, we have characterized the adjuvant activities of CTA1 and LTA1 using HIV and SIV genes as model antigens. Both of these adjuvants enhanced the magnitude of antigen-specific cellular immune responses on par with those induced by the well-characterized cytokine adjuvants IL-12 and GM-CSF. CTA1 and LTA1 preferentially enhanced cellular responses to the intracellular antigen SIVmac239-gag over those for the secreted HIVBaL-gp120 antigen. IL-12, GM-CSF and electroporation did the opposite suggesting differences in the mechanisms of actions of these diverse adjuvants. Combinations of CTA1 or LTA1 with IL-12 or GM-CSF generated additive and better balanced cellular responses to both of these antigens. Consistent with observations made with the holotoxin and the CTA1-DD adjuvant, CTA1 and LTA1 evoked mixed Th1/Th17 cellular immune responses. Together, these results show that CTA1 and LTA1 are potent DNA vaccine adjuvants that favor the intracellular antigen gag over the secreted antigen gp120 and evoke mixed Th1/Th17 responses against both of these antigens. The results also indicate that achieving a balanced immune response to multiple intracellular and extracellular antigens delivered via DNA vaccination may require combining adjuvants that have different and complementary mechanisms of action. PMID:26042527

Adverse Outcome Pathways and Extrapolation Tools to Advance the Three Rs in Ecotoxicology

EPA Science Inventory

Adverse outcome pathways (AOPs) are conceptual frameworks for identifying and organizing predictive and causal linkages between cellular-level responses and endpoints conventionally considered in ecological risk assessment (e.g., effects on survival, growth/development, and repro...

Evaluation of Cytotoxic Responses Caused by Selected Organophosphorus Esters in Chick Sympathetic Ganglia Cultures

PubMed Central

Obersteiner, E. J.; Sharma, R. P.

1978-01-01

Ten day old chick sympathetic ganglia cultured in a microslide assembly were treated with a selected group of organophosphate pesticides to evaluate their cytotoxicity ranges, and the usefulness of such a model for screening pesticides. Examination by phase contrast and light microscopy for chemically-induced morphological alteration of nerve fibers, glial cells and neurons provided the criteria for quantitation and assessment of the toxic effects. Concentrations that produced half-maximal effects ranged from 1 × 10-6M (severely toxic) for methylparathian, diazinon, paraoxon, mevinphos, diisopropylfluorophosphate, tri-o-tolyl phosphate and its mixed isomers to a 1 × 10-3M (intermediate) for malathion, leptophos, coumaphos, mono- and dicrotophos. Some or no effects were evident at 1 × 102-M for O'ethyl-O-p-nitrophenyl phenyl phosphonothioate, tri-m-tolylphosphate, chlorpyriphos and triphenyl phosphate. In all instances, nerve fibers were more sensitive than neurons or glial cells to insecticides. All cellular growth was inhibited at 1 × 10-2M (except triphenyl phosphate). Below 1 x 10-7M, no inhibitory effects were evident. The secondary abnormalities included decreased cellular migration, diffuse cellular growth pattern, increased vacuolization, nerve fiber swelling and cellular degeneration. The cytotoxic effects of these chemicals do not appear to be related to in vivo toxicity or cholinesterase inhibition potential. ImagesFig. 1.Fig. 2.Fig. 3.Fig. 4.Fig. 5.Fig. 6. PMID:565668

Biological Effects of Atomic Radiations; ACCIONES BIOLOGICAS DE LAS RADIACIONES ATOMICAS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Patetta-Queirolo, M.A.

1959-02-01

A resume is presented of each class in a course on the biological effects of nuclear radiations. The topics discussed include the physical and chemical bases of radiation effects, primary and secondary processes, accumulated effects, biochemical and cellular effects, radiation effects on living organisms and tissues, radioecology, genetic effects, cytogenetic effects, genetics of radiation in mammals, response of mammals to irradiation, dosimetry, and protection against radiations. (J.S.R.)

Effects of microwave (2.45 GHz) irradiation on some biological characters of Salmonella typhimurium.

PubMed

Nasri, Kaouther; Daghfous, Douraid; Landoulsi, Ahmed

2013-04-01

The present study was carried out to evaluate the effects of sub-lethal doses of microwave radiation on some biological characteristics in Salmonella typhimurium. The aim was to show the relationship between this treatment and the development of radiotolerance in this pathogen because there is a need for more information on physiological responses of pathogens to sub-lethal doses of microwave radiation. So, the bacterial strain was treated with a dose of 3600J (40-s exposure with power P=90 W) to cause cellular damage. The results have shown that the exposure of bacteria to microwaves resulted in a significant inhibition of cellular growth. This treatment has notably increased the effectiveness of the most tested antibiotics by the amelioration or the appearance of sensitivity in exposed bacteria. Gas chromatography (GC) analysis was performed to demonstrate the modification of the fatty acids (FA) composition. Results obtained have shown that this treatment had a significant effect on the FA content with an increase of unsaturated FA percentage. The acquisition of sensitivity to the sodium deoxycholate and the significant increase in the amount of extracellular proteins in exposed bacteria has confirmed the weakening of the bacterial membrane by microwaves. This study represents one of the few demonstrating the modifications on the bacterial membrane as a cellular response to survive the non-ionising radiation stress. Copyright © 2013 Académie des sciences. Published by Elsevier SAS. All rights reserved.

Humoral and cellular immunity in chromium picolinate-supplemented lambs.

PubMed

Dallago, B S L; McManus, C M; Caldeira, D F; Campeche, A; Burtet, R T; Paim, T P; Gomes, E F; Branquinho, R P; Braz, S V; Louvandini, H

2013-08-01

The effects of oral supplementation of chromium picolinate (CrPic) on humoral and cellular immunity in sheep were investigated. Twenty-four male lambs divided into four treatments and received different dosages of CrPic: placebo (0), 0.250, 0.375, and 0.500 mg of chromium/animal/day during 84 days. The base ration was Panicum maximum cv Massai hay and concentrate. Blood samples were collected fortnightly for total and differential leukocyte counts. On days 28 and 56, the lambs were challenged with chicken ovalbumin I.M. Serum samples were collected on days 46 and 74 and subjected to an indirect enzyme-linked immunosorbent assay to measure IgG anti-ovalbumin. The cell-mediated immune response was determined by a delay-type hypersensitivity test using phytohemagglutinin. CrPic did not significantly affect humoral immunity in lambs but there was a negative effect on cellular immunity (P < 0.05) as Cr supplementation increased. Therefore, the level of Cr supplementation for lambs must be better studied to address its effect on stressed animals or the possible toxic effects of Cr on the animal itself or its immune system.

Chronic kidney disease alters lipid trafficking and inflammatory responses in macrophages: effects of liver X receptor agonism.

PubMed

Kaseda, Ryohei; Tsuchida, Yohei; Yang, Hai-Chun; Yancey, Patricia G; Zhong, Jianyong; Tao, Huan; Bian, Aihua; Fogo, Agnes B; Linton, Mac Rae F; Fazio, Sergio; Ikizler, Talat Alp; Kon, Valentina

2018-01-27

Our aim was to evaluate lipid trafficking and inflammatory response of macrophages exposed to lipoproteins from subjects with moderate to severe chronic kidney disease (CKD), and to investigate the potential benefits of activating cellular cholesterol transporters via liver X receptor (LXR) agonism. LDL and HDL were isolated by sequential density gradient ultracentrifugation of plasma from patients with stage 3-4 CKD and individuals without kidney disease (HDL CKD and HDL Cont , respectively). Uptake of LDL, cholesterol efflux to HDL, and cellular inflammatory responses were assessed in human THP-1 cells. HDL effects on inflammatory markers (MCP-1, TNF-α, IL-1β), Toll-like receptors-2 (TLR-2) and - 4 (TLR-4), ATP-binding cassette class A transporter (ABCA1), NF-κB, extracellular signal regulated protein kinases 1/2 (ERK1/2) were assessed by RT-PCR and western blot before and after in vitro treatment with an LXR agonist. There was no difference in macrophage uptake of LDL isolated from CKD versus controls. By contrast, HD CKD was significantly less effective than HDL Cont in accepting cholesterol from cholesterol-enriched macrophages (median 20.8% [IQR 16.1-23.7] vs control (26.5% [IQR 19.6-28.5]; p = 0.008). LXR agonist upregulated ABCA1 expression and increased cholesterol efflux to HDL of both normal and CKD subjects, although the latter continued to show lower efflux capacity. HDL CKD increased macrophage cytokine response (TNF-α, MCP-1, IL-1β, and NF-κB) versus HDL Cont . The heightened cytokine response to HDL CKD was further amplified in cells treated with LXR agonist. The LXR-augmentation of inflammation was associated with increased TLR-2 and TLR-4 and ERK1/2. Moderate to severe impairment in kidney function promotes foam cell formation that reflects impairment in cholesterol acceptor function of HDL CKD . Activation of cellular cholesterol transporters by LXR agonism improves but does not normalize efflux to HDL CKD . However, LXR agonism actually increases the pro-inflammatory effects of HDL CKD through activation of TLRs and ERK1/2 pathways.

Developmental and light regulation of tumor suppressor protein PP2A in the retina

PubMed Central

Rajala, Ammaji; Wang, Yuhong; Abcouwer, Steven F.; Gardner, Thomas W.; Rajala, Raju V.S.

2018-01-01

Protein phosphatases are a group of universal enzymes that are responsible for the dephosphorylation of various proteins and enzymes in cells. Cellular signal transduction events are largely governed by the phosphorylation of key proteins. The length of cellular response depends on the activation of protein phosphatase that dephosphorylates the phosphate groups to halt a biological response, and fine-tune the defined cellular outcome. Dysregulation of these phosphatase(s) results in various disease phenotypes. The retina is a post-mitotic tissue, and oncogenic tyrosine and serine/ threonine kinase activities are important for retinal neuron survival. Aberrant activation of protein phosphatase(s) may have a negative effect on retinal neurons. In the current study, we characterized tumor suppressor protein phosphatase 2 (PP2A), a major serine/ threonine kinase with a broad substrate specificity. Our data suggest that PP2A is developmentally regulated in the retina, localized predominantly in the inner retina, and expressed in photoreceptor inner segments. Our findings indicate that PKCα and mTOR may serve as PP2A substrates. We found that light regulates PP2A activity. Our studies also suggest that rhodopsin regulates PP2A and its substrate(s) dephosphorylation. PP2A substrate phosphorylation is increased in mice lacking the A-subunit of PP2A. However, there is no accompanying effect on retina structure and function. Together, our findings suggest that controlling the activity of PP2A in the retina may be neuroprotective. PMID:29416710

Apoptosis in response to heat stress is positively associated with heat-shock protein 90 expression in chicken myocardial cells in vitro.

PubMed

Zhang, Xiao-Hui; Wu, Hong; Tang, Shu; Li, Qiao-Ning; Xu, Jiao; Zhang, Miao; Su, Ya-Nan; Yin, Bin; Zhao, Qi-Ling; Kemper, Nicole; Hartung, Joerg; Bao, En-Dong

2017-06-30

To determine heat-shock protein (Hsp)90 expression is connected with cellular apoptotic response to heat stress and its mechanism, chicken ( Gallus gallus ) primary myocardial cells were treated with the Hsp90 promoter, aspirin, and its inhibitor, geldanamycin (GA), before heat stress. Cellular viability, heat-stressed apoptosis and reactive oxygen species level under different treatments were measured, and the expression of key proteins of the signaling pathway related to Hsp90 and their colocalization with Hsp90 were detected. The results showed that aspirin treatment increased the expression of protein kinase B (Akt), the signal transducer and activator of transcription (STAT)-3 and p-IKKα/β and the colocalization of Akt and STAT-3 with Hsp90 during heat stress, which was accompanied by improved viability and low apoptosis. GA significantly inhibited Akt expression and p-IKKα/β level, but not STAT-3 quantity, while the colocalization of Akt and STAT-3 with Hsp90 was weakened, followed by lower cell viability and higher apoptosis. Aspirin after GA treatment partially improved the stress response and apoptosis rate of tested cells caused by the recovery of Akt expression and colocalization, rather than the level of STAT-3 (including its co-localization with Hsp90) and p-IKKα/β. Therefore, Hsp90 expression has a positive effect on cellular capacity to resist heat-stressed injury and apoptosis. Moreover, inhibition of Hsp90 before stress partially attenuated its positive effects.

Neurotoxic lupus autoantibodies alter brain function through two distinct mechanisms

PubMed Central

Faust, Thomas W.; Chang, Eric H.; Kowal, Czeslawa; Berlin, RoseAnn; Gazaryan, Irina G.; Bertini, Eva; Zhang, Jie; Sanchez-Guerrero, Jorge; Fragoso-Loyo, Hilda E.; Volpe, Bruce T.; Diamond, Betty; Huerta, Patricio T.

2010-01-01

Damaging interactions between antibodies and brain antigenic targets may be responsible for an expanding range of neurological disorders. In the case of systemic lupus erythematosus (SLE), patients generate autoantibodies (AAbs) that frequently bind dsDNA. Although some symptoms of SLE may arise from direct reactivity to dsDNA, much of the AAb-mediated damage originates from cross-reactivity with other antigens. We have studied lupus AAbs that bind dsDNA and cross-react with the NR2A and NR2B subunits of the NMDA receptor (NMDAR). In adult mouse models, when the blood–brain barrier is compromised, these NMDAR-reactive AAbs access the brain and elicit neuronal death with ensuing cognitive dysfunction and emotional disturbance. The cellular mechanisms that underlie these deleterious effects remain incompletely understood. Here, we show that, at low concentration, the NMDAR-reactive AAbs are positive modulators of receptor function that increase the size of NMDAR-mediated excitatory postsynaptic potentials, whereas at high concentration, the AAbs promote excitotoxicity through enhanced mitochondrial permeability transition. Other synaptic receptors are completely unaffected by the AAbs. NMDAR activation is required for producing both the synaptic and the mitochondrial effects. Our study thus reveals the mechanisms by which NMDAR-reactive AAbs trigger graded cellular alterations, which are likely to be responsible for the transient and permanent neuropsychiatric symptoms observed in patients with SLE. Our study also provides a model in which local AAb concentration determines the exact nature of the cellular response. PMID:20921396

Clinical factors that influence the cellular responses of saphenous veins used for arterial bypass.

PubMed

Sobel, Michael; Kikuchi, Shinsuke; Chen, Lihua; Tang, Gale L; Wight, Tom N; Kenagy, Richard D

2018-06-15

When an autogenous vein is harvested and used for arterial bypass, it suffers physical and biologic injuries that may set in motion the cellular processes that lead to wall thickening, fibrosis, stenosis, and ultimately graft failure. Whereas the injurious effects of surgical preparation of the vein conduit have been extensively studied, little is known about the influence of the clinical environment of the donor leg from which the vein is obtained. We studied the cellular responses of fresh saphenous vein samples obtained before implantation in 46 patients undergoing elective lower extremity bypass surgery. Using an ex vivo model of response to injury, we quantified the outgrowth of cells from explants of the adventitial and medial layers of the vein. We correlated this cellular outgrowth with the clinical characteristics of the patients, including the Wound, Ischemia, and foot Infection classification of the donor leg for ischemia, wounds, and infection as well as smoking and diabetes. Cellular outgrowth was significantly faster and more robust from the adventitial layer than from the medial layer. The factors of leg ischemia (P < .001), smoking (P = .042), and leg infection (P = .045) were associated with impaired overall outgrowth from the adventitial tissue on multivariable analysis. Only ischemia (P = .046) was associated with impaired outgrowth of smooth muscle cells (SMCs) from the medial tissue. Co-culture of adventitial cells and SMCs propagated from vein explants revealed that adventitial cells significantly inhibited the growth of SMCs, whereas SMCs promoted the growth of adventitial cells. The AA genotype of the -838C>A p27 polymorphism (previously associated with superior graft patency) enhanced these effects, whereas the factor of smoking attenuated adventitial cell inhibition of SMC growth. Comparing gene expression, the cells cultured from the media overexpress Kyoto Encyclopedia of Genes and Genomes pathways associated with inflammation and infection, whereas those from the adventitia overexpress gene families associated with development and stem/progenitor cell maintenance. The adverse clinical environment of the leg may influence the biologic behavior of the cells in the vein wall, especially the adventitial cells. Chronic ischemia was the most significant factor that retards adventitial cell outgrowth. The cells arising from the vein adventitia may be key players in determining a healthy adaptive or a pathologic response to the injuries associated with vein grafting. Copyright © 2018 Society for Vascular Surgery. All rights reserved.

Immunological tools for the assessment of both humoral and cellular immune responses in Foxes (Vulpes vulpes) using ovalbumin and cholera toxin B as an antigenic model.

PubMed

Rolland-Turner, Magali; Farre, Guillaume; Muller, Delphine; Rouet, Nelly; Boue, Franck

2004-10-22

The immune response in the fox (Vulpes vulpes), despite the success of the oral rabies vaccine is not well characterized, and specific immunological tools are needed. To investigate both the humoral and cellular immune response, we used ovalbumin (OVA) and cholera toxin B (CTB) as an antigenic model to set-up ELISA and ELISPOT antibodies secreting cells (ASC) assays in the fox model. Identification of antibodies that cross-react with fox immunoglobulin was performed by Western blot, and their use was adapted for both the ELISA and ELISPOT ASC assay. The humoral and cellular specific immune responses were assessed after intra-muscular or intra-nasal immunization. Intra-muscular immunization resulted in the development of both cellular and humoral anti-OVA and anti-CTB responses in peripheral blood mononuclear cells (PBMCs). Immunization via the intra-nasal route resulted in the development of a cellular and humoral response against CTB in PBMCs. This immune response was confirmed using splenocytes from immunized animals by ELISPOT assay at euthanasia. Females immunized via the intra-nasal route developed specific anti-CTB IgM, IgA and IgG in vaginal fluids after the initial boost (day 26) showing that mucosal immunization produces a vaginal immune response in foxes. These immunological tools developed here are now available to be adapted to other antigenic models to facilitate further immune studies in foxes.

Genetic variants in cellular transport do not affect mesalamine response in ulcerative colitis

PubMed Central

Huang, Hailiang; Rivas, Manuel; Kaplan, Jess L.; Daly, Mark J.; Winter, Harland S.

2018-01-01

Background and aims Mesalamine is commonly used to treat ulcerative colitis (UC). Although mesalamine acts topically, in vitro data suggest that intracellular transport is required for its beneficial effect. Genetic variants in mucosal transport proteins may affect this uptake, but the clinical relevance of these variants has not been studied. The aim of this study was to determine whether variants in genes involved in cellular transport affect the response to mesalamine in UC. Methods Subjects with UC from a 6-week clinical trial using multiple doses of mesalamine were genotyped using a genome-wide array that included common exome variants. Analysis focused on cellular transport gene variants with a minor allele frequency >5%. Mesalamine response was defined as improvement in Week 6 Physician’s Global Assessment (PGA) and non-response as a lack of improvement in Week 6 PGA. Quality control thresholds included an individual genotyping rate of >90%, SNP genotyping rate of >98%, and exclusion for subjects with cryptic relatedness. All included variants met Hardy-Weinberg equilibrium (p>0.001). Results 457 adults with UC were included with 280 responders and 177 non-responders. There were no common variants in transporter genes that were associated with response to mesalamine. The genetic risk score of responders was similar to that of non-responders (p = 0.18). Genome-wide variants demonstrating a trend towards mesalamine response included ST8SIA5 (p = 1x10-5). Conclusions Common transporter gene variants did not affect response to mesalamine in adult UC. The response to mesalamine may be due to rare genetic events or environmental factors such as the intestinal microbiome. PMID:29579042

HIV Gag protein conjugated to a Toll-like receptor 7/8 agonist improves the magnitude and quality of Th1 and CD8+ T cell responses in nonhuman primates

NASA Astrophysics Data System (ADS)

Wille-Reece, Ulrike; Flynn, Barbara J.; Loré, Karin; Koup, Richard A.; Kedl, Ross M.; Mattapallil, Joseph J.; Weiss, Walter R.; Roederer, Mario; Seder, Robert A.

2005-10-01

Induction and maintenance of antibody and T cell responses will be critical for developing a successful vaccine against HIV. A rational approach for generating such responses is to design vaccines or adjuvants that have the capacity to activate specific antigen-presenting cells. In this regard, dendritic cells (DCs) are the most potent antigen-presenting cells for generating primary T cell responses. Here, we report that Toll-like receptor (TLR) agonists and ligands that activate DCs in vitro influence the magnitude and quality of the cellular immune response in nonhuman primates (NHPs) when administered with HIV Gag protein. NHPs immunized with HIV Gag protein and a TLR7/8 agonist or a TLR9 ligand [CpG oligodeoxynucleotides (CpG ODN)] had significantly increased Gag-specific T helper 1 and antibody responses, compared with animals immunized with HIV Gag protein alone. Importantly, conjugating the HIV Gag protein to the TLR7/8 agonist (Gag-TLR7/8 conjugate) dramatically enhanced the magnitude and altered the quality of the T helper 1 response, compared with animals immunized with HIV Gag protein and the TLR7/8 agonist or CpG ODN. Furthermore, immunization with the Gag-TLR7/8 conjugate vaccine elicited Gag-specific CD8+ T responses. Collectively, our results show that conjugating HIV Gag protein to a TLR7/8 agonist is an effective way to elicit broad-based adaptive immunity in NHPs. This type of vaccine formulation should have utility in preventive or therapeutic vaccines in which humoral and cellular immunity is required. vaccine | dendritic cell | cross-presentation | cellular immunity

Dose-dependent intracellular reactive oxygen and nitrogen species (ROS/RNS) production from particulate matter exposure: comparison to oxidative potential and chemical composition

NASA Astrophysics Data System (ADS)

Tuet, Wing Y.; Fok, Shierly; Verma, Vishal; Tagle Rodriguez, Marlen S.; Grosberg, Anna; Champion, Julie A.; Ng, Nga L.

2016-11-01

Elevated particulate matter (PM) concentrations have been associated with cardiopulmonary risks. In this study, alveolar macrophages and ventricular myocytes were exposed to PM extracts from 104 ambient filters collected in multiple rural and urban sites in the greater Atlanta area. PM-induced reactive oxygen/nitrogen species (ROS/RNS) were measured to investigate the effect of chemical composition and determine whether chemical assays are representative of cellular responses. For summer samples, the area under the ROS/RNS dose-response curve per volume of air (AUCvolume) was significantly correlated with dithiothreitol (DTT) activity, water-soluble organic carbon (WSOC), brown carbon, titanium, and iron, while a relatively flat response was observed for winter samples. EC50 was also correlated with max response for all filters investigated, which suggests that certain PM constituents may be involved in cellular protective pathways. Although few metal correlations were observed, exposure to laboratory-prepared metal solutions induced ROS/RNS production, indicating that a lack of correlation does not necessarily translate to a lack of response. Collectively, these results suggest that complex interactions may occur between PM species. Furthermore, the strong correlation between organic species and ROS/RNS response highlights a need to understand the contribution of organic aerosols, especially photochemically driven secondary organic aerosols (SOA), to PM-induced health effects.

Wet-Lay Process - A Novel Approach to Scalable Fabrication of Tissue Scaffolds and Reinforcement Membranes

NASA Astrophysics Data System (ADS)

Wood, Andrew

Fibrous materials received a great deal of interest in the fields of tissue engineering and regenerative medicine due to the beneficial cell-interactions and tunable properties for various biomedical applications. These materials are highly advantageous as they provide a large surface area for cellular attachment, proliferation, high porosity values for cellular in-growth, and the ability to modify the membrane to achieve desired responses to both mechanical loading as well as environmental stimuli. A prominent method currently used to fabricate such membranes is electrospinning which uses electrostatic forces to produce fibers on the range of nanometers giving them high morphological saliency to the native extra cellular matrix (ECM). These fibers are also advantageous mechanically with strength and flexibility due to their larger aspect ratio when compared to larger diameter micro/macro fibers. While this spinning technique has many advantages and has seen the most quantity of research in recent years, it does have its own set of drawbacks. Among them is the use cytotoxic solvents during processing which must be fully removed before implantation. In addition, since the fiber produced have smaller diameters, the resulting average pore-size of the scaffold is decreased which in turn hinders cellular penetration into the bulk scaffold. In this work, we have proposed and characterized a novel method called wet-lay process for the rapid fabrication of fibrous membranes for tissue scaffolds. Wet-laying is a method common to textiles and paper industry but unexplored for tissue scaffolds. Short fibers are first suspended in an aqueous bath and homogeneously dispersed using shear force. After draining away the aqueous solution, a nonwoven fibro-porous membrane is deposited onto the draining screen. The implementation of wet-laid membranes into weak hydrogel matrices has shown a reinforcement effect for the composite. Further analyses were carried out to determine the synergistic effect that fiber-length and fiber-concentration have on the dispersion of the fibers during fabrication and cellular response as well as the mechanical reinforcement within a hydrogel matrix. Finally, a method is proposed and validated to both strengthen the as-fabricated membrane as well as to introduce a complex pore-size gradient throughout the scaffold so that cellular response on the bi-layer scaffolds can be modified according to a particular application.

[Cellular transplantation laboratory: a new field of action for nurses].

PubMed

Corradi, Maria Inês; da Silva, Sandra Honorato

2008-01-01

This article presents the experience of a nurse at a cellular transplantation laboratory. This laboratory goal is to isolate insulin producing cells for human transplantation. The nurse, as a member of an interdisciplinary team, took part in the planning of all work processes: working procedures and team training. The main activities under the nurse responsibilities include contamination control, on-the-job training and evaluation of the Quality of the procedures developed by the interdisciplinary team. Results have shown the effectiveness of the nurses' work in this new field.

Conference on Correlations of Aging and Space Effects on Biosystems, Oct. 30-Nov. 1, 1989, Proceedings

NASA Technical Reports Server (NTRS)

Sprott, Richard L. (Editor); Combs, Carol A. (Editor)

1991-01-01

This volume includes papers on correlations between aging effects and space effects on biosystems, with particular attention given to the effects on the cardiovascular system, bone, sleep, cellular systems, immunological system, and genetics. Papers are presented on NASA and NIA plans and opportunities, the age effect on the posture and circulation, the cardiovascular physiology in space flight, and age-related bone changes. Attention is given to research on sleep, circulation rhythms, and aging and its applications to manned spaceflight; sleep and circadian rhythms; altered cell function in microgravity; and the heterogeneity of changes in lymphoproliferative ability with increasing age. Also included is a review of cellular immunosenescence, a paper on the immune response during space flight, and a paper on Caenorhabditis elegans as a model system for space biology studies.

Intracellular drug delivery nanocarriers of glutathione-responsive degradable block copolymers having pendant disulfide linkages.

PubMed

Khorsand, Behnoush; Lapointe, Gabriel; Brett, Christopher; Oh, Jung Kwon

2013-06-10

Self-assembled micelles of amphiphilic block copolymers (ABPs) with stimuli-responsive degradation (SRD) properties have a great promise as nanotherapeutics exhibiting enhanced release of encapsulated therapeutics into targeted cells. Here, thiol-responsive degradable micelles based on a new ABP consisting of a pendant disulfide-labeled methacrylate polymer block (PHMssEt) and a hydrophilic poly(ethylene oxide) (PEO) block were investigated as effective intracellular nanocarriers of anticancer drugs. In response to glutathione (GSH) as a cellular trigger, the cleavage of pendant disulfide linkages in hydrophobic PHMssEt blocks of micellar cores caused the destabilization of self-assembled micelles due to change in hydrophobic/hydrophilic balance. Such GSH-triggered micellar destabilization changed their size distribution with an appearance of large aggregates and led to enhanced release of encapsulated anticancer drugs. Cell culture results from flow cytometry and confocal laser scanning microscopy for cellular uptake as well as cell viability measurements for high anticancer efficacy suggest that new GSH-responsive degradable PEO-b-PHMssEt micelles offer versatility in multifunctional drug delivery applications.

Slight temperature changes affect protein affinity and cellular uptake/toxicity of nanoparticles

NASA Astrophysics Data System (ADS)

Mahmoudi, Morteza; Shokrgozar, Mohammad A.; Behzadi, Shahed

2013-03-01

It is known that what the cell actually ``sees'' at the nanoscale is an outer shell formed of `protein corona' on the surface of nanoparticles (NPs). The amount and composition of various proteins on the corona are strongly dependent on the biophysicochemical properties of NPs, which have been extensively studied. However, the effect of a small variation in temperature, due to the human circadian rhythm, on the composition of the protein corona and the affinity of various proteins to the surface of NPs, was ignored. Here, the effect of temperature on the composition of protein corona and the affinity of various proteins to the surface of NPs and, subsequently, cell responses to the protein coated NPs are probed. The results confirmed that cellular entrance, dispersion, and toxicity of NPs are strongly diverse with slight body temperature changes. This new finding can help scientists to maximise NP entrance to specific cells/organs with lower toxicity by adjusting the cellular/organ temperature.It is known that what the cell actually ``sees'' at the nanoscale is an outer shell formed of `protein corona' on the surface of nanoparticles (NPs). The amount and composition of various proteins on the corona are strongly dependent on the biophysicochemical properties of NPs, which have been extensively studied. However, the effect of a small variation in temperature, due to the human circadian rhythm, on the composition of the protein corona and the affinity of various proteins to the surface of NPs, was ignored. Here, the effect of temperature on the composition of protein corona and the affinity of various proteins to the surface of NPs and, subsequently, cell responses to the protein coated NPs are probed. The results confirmed that cellular entrance, dispersion, and toxicity of NPs are strongly diverse with slight body temperature changes. This new finding can help scientists to maximise NP entrance to specific cells/organs with lower toxicity by adjusting the cellular/organ temperature. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr32551b

Drosophila cellular immunity: a story of migration and adhesion.

PubMed

Fauvarque, Marie-Odile; Williams, Michael J

2011-05-01

Research during the past 15 years has led to significant breakthroughs, providing evidence of a high degree of similarity between insect and mammalian innate immune responses, both humoural and cellular, and highlighting Drosophila melanogaster as a model system for studying the evolution of innate immunity. In a manner similar to cells of the mammalian monocyte and macrophage lineage, Drosophila immunosurveillance cells (haemocytes) have a number of roles. For example, they respond to wound signals, are involved in wound healing and contribute to the coagulation response. Moreover, they participate in the phagocytosis and encapsulation of invading pathogens, are involved in the removal of apoptotic bodies and produce components of the extracellular matrix. There are several reasons for using the Drosophila cellular immune response as a model to understand cell signalling during adhesion and migration in vivo: many genes involved in the regulation of Drosophila haematopoiesis and cellular immunity have been maintained across taxonomic groups ranging from flies to humans, many aspects of Drosophila and mammalian innate immunity seem to be conserved, and Drosophila is a simplified and well-studied genetic model system. In the present Commentary, we will discuss what is known about cellular adhesion and migration in the Drosophila cellular immune response, during both embryonic and larval development, and where possible compare it with related mechanisms in vertebrates.

Spores of two probiotic Bacillus species enhance cellular immunity in BALB/C mice.

PubMed

Gong, Li; Huang, Qin; Fu, Aikun; Wu, YanPing; Li, Yali; Xu, Xiaogang; Huang, Yi; Yu, Dongyou; Li, Weifen

2018-01-01

Previous studies found that Bacillus subtilis BS02 and B. subtilis subsp. natto BS04 isolated in our laboratory could activate the immune response of murine macrophages in vitro. This study aims to investigate the effects of dietary supplementation with Bacillus species spores on the systemic cellular immune response in BALB/C mice. Results showed that both B. subtilis BS02 and B. subtilis natto BS04 enhanced the phagocytic function of the mononuclear phagocyte system (MPS) and the cytotoxicity of natural killer (NK) cells. In addition, B. subtilis BS02 could increase the respiratory burst activity of blood phagocytes. Furthermore, B. subtilis BS02 and B. subtilis natto BS04 increased the percentage of gamma-interferon-producing CD4 + cells and CD8 + T-cells, but only BS04 increased the percentage of CD3 + cells and CD3 +  CD4 + cells in splenocytes. However, there were no effects on other subsets of splenic lymphocytes and mitogen-induced splenic lymphocyte proliferation. All data suggested that oral administration of B. subtilis BS02 or B. subtilis natto BS04 could significantly enhance cellular immunity in BALB/C mice by increasing phagocytic activity of MPS and cytotoxic activity of NK cells in a strain-specific manner.

Biosynthetic hydrogels--studies on chemical and physical characteristics on long-term cellular response for tissue engineering.

PubMed

Thankam, Finosh Gnanaprakasam; Muthu, Jayabalan

2014-07-01

Biosynthetic hydrogels can meet the drawbacks caused by natural and synthetic ones for biomedical applications. In the current article we present a novel biosynthetic alginate-poly(propylene fumarate) copolymer based chemically crosslinked hydrogel scaffolds for cardiac tissue engineering applications. Partially crosslinked PA hydrogel and fully cross linked PA-A hydrogel scaffolds were prepared. The influence of chemical and physical (morphology and architecture of hydrogel) characteristics on the long term cellular response was studied. Both these hydrogels were cytocompatible and showed no genotoxicity upon contact with fibroblast cells. Both PA and PA-A were able to resist deleterious effects of reactive oxygen species and sustain the viability of L929 cells. The hydrogel incubated oxidative stress induced cells were capable of maintaining the intra cellular reduced glutathione (GSH) expression to the normal level confirmed their protective effect. Relatively the PA hydrogel was found to be unstable in the cell culture medium. The PA-A hydrogel was able to withstand appreciable cyclic stretching. The cyclic stretching introduced complex macro and microarchitectural features with interconnected pores and more structured bound water which would provide long-term viability of around 250% after the 24th day of culture. All these qualities make PA-A hydrogel form a potent candidate for cardiac tissue engineering. © 2013 Wiley Periodicals, Inc.

The host immunological response to cancer therapy: An emerging concept in tumor biology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Voloshin, Tali; Voest, Emile E.; Shaked, Yuval, E-mail: yshaked@tx.technion.ac.il

Almost any type of anti-cancer treatment including chemotherapy, radiation, surgery and targeted drugs can induce host molecular and cellular immunological effects which, in turn, can lead to tumor outgrowth and relapse despite an initial successful therapy outcome. Tumor relapse due to host immunological effects is attributed to angiogenesis, tumor cell dissemination from the primary tumors and seeding at metastatic sites. This short review will describe the types of host cells that participate in this process, the types of factors secreted from the host following therapy that can promote tumor re-growth, and the possible implications of this unique and yet onlymore » partially-known process. It is postulated that blocking these specific immunological effects in the reactive host in response to cancer therapy may aid in identifying new host-dependent targets for cancer, which in combination with conventional treatments can prolong therapy efficacy and extend survival. Additional studies investigating this specific research direction—both in preclinical models and in the clinical setting are essential in order to advance our understanding of how tumors relapse and evade therapy. -- Highlights: • Cancer therapy induces host molecular and cellular pro-tumorigenic effects. • Host effects in response to therapy may promote tumor relapse and metastasis. • The reactive host consists of immunological mediators promoting tumor re-growth. • Blocking therapy-induced host mediators may improve outcome.« less

SYMPOSIUM SESSION PROPOSAL: INCORPORATION OF MODE OF ACTION INTO MECHANISTICALLY-BASED QUANTITATIVE MODELS

EPA Science Inventory

The biological processes by which environmental pollutants induce adverse health effects is most likely regulated by complex interactions dependent upon the route of exposure, dose, kinetics of distribution, and multiple cellular responses. To further complicate deciphering thes...

Biomarkers and Environmental Stress: Relevance of Cellular Responses in Determining Adverse Outcomes

EPA Science Inventory

Biomarkers are measurable changes in a biological system indicative of an interaction with a chemical, physical, or biological agent. Such changes can be molecular, biochemical, physiological, or histological and can be reflective of either xenobiotic exposures or effects. Molecu...

A Cellular Game of Telephone: Trans Tissue Reprogramming of Responses to Toxic Stimuli

EPA Science Inventory

Exposure to air pollution is a leading cause of cardiopulmonary morbidity and mortality; however, while these effects outside the lung have been associated with aberrant oxidative stress and inflammation, the underlying molecular mechanisms are poorly understood. We hypothesized ...

Multiplicity of Mathematical Modeling Strategies to Search for Molecular and Cellular Insights into Bacteria Lung Infection

PubMed Central

Cantone, Martina; Santos, Guido; Wentker, Pia; Lai, Xin; Vera, Julio

2017-01-01

Even today two bacterial lung infections, namely pneumonia and tuberculosis, are among the 10 most frequent causes of death worldwide. These infections still lack effective treatments in many developing countries and in immunocompromised populations like infants, elderly people and transplanted patients. The interaction between bacteria and the host is a complex system of interlinked intercellular and the intracellular processes, enriched in regulatory structures like positive and negative feedback loops. Severe pathological condition can emerge when the immune system of the host fails to neutralize the infection. This failure can result in systemic spreading of pathogens or overwhelming immune response followed by a systemic inflammatory response. Mathematical modeling is a promising tool to dissect the complexity underlying pathogenesis of bacterial lung infection at the molecular, cellular and tissue levels, and also at the interfaces among levels. In this article, we introduce mathematical and computational modeling frameworks that can be used for investigating molecular and cellular mechanisms underlying bacterial lung infection. Then, we compile and discuss published results on the modeling of regulatory pathways and cell populations relevant for lung infection and inflammation. Finally, we discuss how to make use of this multiplicity of modeling approaches to open new avenues in the search of the molecular and cellular mechanisms underlying bacterial infection in the lung. PMID:28912729

Multiplicity of Mathematical Modeling Strategies to Search for Molecular and Cellular Insights into Bacteria Lung Infection.

PubMed

Cantone, Martina; Santos, Guido; Wentker, Pia; Lai, Xin; Vera, Julio

2017-01-01

Even today two bacterial lung infections, namely pneumonia and tuberculosis, are among the 10 most frequent causes of death worldwide. These infections still lack effective treatments in many developing countries and in immunocompromised populations like infants, elderly people and transplanted patients. The interaction between bacteria and the host is a complex system of interlinked intercellular and the intracellular processes, enriched in regulatory structures like positive and negative feedback loops. Severe pathological condition can emerge when the immune system of the host fails to neutralize the infection. This failure can result in systemic spreading of pathogens or overwhelming immune response followed by a systemic inflammatory response. Mathematical modeling is a promising tool to dissect the complexity underlying pathogenesis of bacterial lung infection at the molecular, cellular and tissue levels, and also at the interfaces among levels. In this article, we introduce mathematical and computational modeling frameworks that can be used for investigating molecular and cellular mechanisms underlying bacterial lung infection. Then, we compile and discuss published results on the modeling of regulatory pathways and cell populations relevant for lung infection and inflammation. Finally, we discuss how to make use of this multiplicity of modeling approaches to open new avenues in the search of the molecular and cellular mechanisms underlying bacterial infection in the lung.

Ultraviolet Radiation: Cellular Antioxidant Response and the Role of Ocular Aldehyde Dehydrogenase Enzymes

PubMed Central

Marchitti, Satori A.; Chen, Ying; Thompson, David C.; Vasiliou, Vasilis

2011-01-01

Solar ultraviolet radiation (UVR) exposes the human eye to near constant oxidative stress. Evidence suggests that UVR is the most important environmental insult leading to the development of a variety of ophthalmoheliosis disorders. UVR-induced reactive oxygen species are highly reactive with DNA, proteins and cellular membranes, resulting in cellular and tissue damage. Antioxidant defense systems present in ocular tissues function to combat reactive oxygen species and protect the eye from oxidative damage. Important enzymatic antioxidants are the superoxide dismutases, catalase, glutathione peroxidases, glutathione reductase and members of the aldehyde dehydrogenase (ALDH) superfamily. Glutathione, ascorbic and uric acids, α-tocopherol, NADPH and ferritin serve as small molecule, nonenzymatic antioxidants. Ocular tissues have high levels of these antioxidants which are essential for the maintenance of redox homeostasis in the eye and protection against oxidative damage. ALDH1A1 and ALDH3A1, present abundantly in the cornea and lens, have been shown to have unique roles in the defense against UVR and the downstream effects of oxidative stress. This review presents the properties and functions of ocular antioxidants that play critical roles in the cellular response to UVR exposure, including a focused discussion of the unique roles that the ALDH1A1 and ALDH3A1 enzymes have as multi-functional ocular antioxidants. PMID:21670692

Redox and pH Dual-Responsive Polymeric Micelles with Aggregation-Induced Emission Feature for Cellular Imaging and Chemotherapy.

PubMed

Zhuang, Weihua; Xu, Yangyang; Li, Gaocan; Hu, Jun; Ma, Boxuan; Yu, Tao; Su, Xin; Wang, Yunbing

2018-05-21

Intelligent polymeric micelles for antitumor drug delivery and tumor bioimaging have drawn a broad attention because of their reduced systemic toxicity, enhanced efficacy of drugs, and potential application of tumor diagnosis. Herein, we developed a multifunctional polymeric micelle system based on a pH and redox dual-responsive mPEG-P(TPE- co-AEMA) copolymer for stimuli-triggered drug release and aggregation-induced emission (AIE) active imaging. These mPEG-P(TPE- co-AEMA)-based micelles showed excellent biocompatibility and emission property, exhibiting great potential application for cellular imaging. Furthermore, the antitumor drug doxorubicin (DOX) could be encapsulated during self-assembly process with high loading efficiency, and a DOX-loaded micelle system with a size of 68.2 nm and narrow size distribution could be obtained. DOX-loaded micelles demonstrated great tumor suppression ability in vitro, and the dual-responsive triggered intracellular drug release could be further traced. Moreover, DOX-loaded micelles could efficiently accumulate at the tumor site because of enhanced permeability and retention effect and long circulation of micelles. Compared with free DOX, DOX-loaded micelles exhibited better antitumor effect and significantly reduced adverse effects. Given the efficient accumulation targeting to tumor tissue, dual-responsive drug release, and excellent AIE property, this polymeric micelle would be a potential candidate for cancer therapy and diagnosis.

Reduced Aβ secretion by human neurons under conditions of strongly increased BACE activity.

PubMed

Scholz, Diana; Chernyshova, Yana; Ückert, Anna-Katharina; Leist, Marcel

2018-05-27

The initial step in the amyloidogenic cascade of amyloid precursor protein (APP) processing is catalyzed by beta-site APP-cleaving enzyme (BACE), and this protease has increased activities in affected areas of Alzheimer's disease brains. We hypothesized that altered APP processing, due to augmented BACE activity, would affect the actions of direct and indirect BACE inhibitors. We therefore compared postmitotic human neurons (LUHMES) with their BACE-overexpressing counterparts (BLUHMES). Although β-cleavage of APP was strongly increased in BLUHMES, they produced less full-length and truncated amyloid beta (Aβ) than LUHMES. Moreover, low concentrations of BACE inhibitors decreased cellular BACE activity as expected, but increased Aβ 1-40 levels. Several other approaches to modulate BACE activity led to a similar, apparently paradoxical, behavior. For instance, reduction of intracellular acidification by bepridil increased Aβ production in parallel with decreased BACE activity. In contrast to BLUHMES, the respective control cells (LUHMES or BLUHMES with catalytically inactive BACE) showed conventional pharmacological responses. Other non-canonical neurochemical responses (so-called 'rebound effects') are well-documented for the Aβ pathway, especially for γ-secretase: a partial block of its activity leads to an increased Aβ secretion by some cell types. We therefore compared LUHMES and BLUHMES regarding rebound effects of γ-secretase inhibitors and found an Aβ rise in LUHMES but not in BLUHMES. Thus, different cellular factors are responsible for the γ-secretase- vs. BACE-related Aβ rebound. We conclude that increased BACE activity, possibly accompanied by an altered cellular localization pattern, can dramatically influence Aβ generation in human neurons and affect pharmacological responses to secretase inhibitors. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Intercellular communication via gap junctions affected by mechanical load in the bovine annulus fibrosus.

PubMed

Desrochers, Jane; Duncan, Neil A

2014-01-01

Cells in the intervertebral disc, as in other connective tissues including tendon, ligament and bone, form interconnected cellular networks that are linked via functional gap junctions. These cellular networks may be necessary to affect a coordinated response to mechanical and environmental stimuli. Using confocal microscopy with fluorescence recovery after photobleaching methods, we explored the in situ strain environment of the outer annulus of an intact bovine disc and the effect of high-level flexion on gap junction signalling. The in situ strain environment in the extracellular matrix of the outer annulus under high flexion load was observed to be non-uniform with the extensive cellular processes remaining crimped sometimes at flexion angles greater than 25°. A significant transient disruption of intercellular communication via functional gap junctions was measured after 10 and 20 min under high flexion load. This study illustrates that in healthy annulus fibrosus tissue, high mechanical loads can impede the functioning of the gap junctions. Future studies will explore more complex loading conditions to determine whether losses in intercellular communication can be permanent and whether gap junctions in aged and degenerated tissues become more susceptible to load. The current research suggests that cellular structures such as gap junctions and intercellular networks, as well as other cell-cell and cell-matrix interconnections, need to be considered in computational models in order to fully understand how macroscale mechanical signals are transmitted across scales to the microscale and ultimately into a cellular biosynthetic response in collagenous tissues.

The agglomeration state of nanoparticles can influence the mechanism of their cellular internalisation.

PubMed

Halamoda-Kenzaoui, Blanka; Ceridono, Mara; Urbán, Patricia; Bogni, Alessia; Ponti, Jessica; Gioria, Sabrina; Kinsner-Ovaskainen, Agnieszka

2017-06-26

Significant progress of nanotechnology, including in particular biomedical and pharmaceutical applications, has resulted in a high number of studies describing the biological effects of nanomaterials. Moreover, a determination of so-called "critical quality attributes", that is specific physicochemical properties of nanomaterials triggering the observed biological response, has been recognised as crucial for the evaluation and design of novel safe and efficacious therapeutics. In the context of in vitro studies, a thorough physicochemical characterisation of nanoparticles (NPs), also in the biological medium, is necessary to allow a correlation with a cellular response. Following this concept, we examined whether the main and frequently reported characteristics of NPs such as size and the agglomeration state can influence the level and the mechanism of NP cellular internalization. We employed fluorescently-labelled 30 and 80 nm silicon dioxide NPs, both in agglomerated and non-agglomerated form. Using flow cytometry, transmission electron microscopy, the inhibitors of endocytosis and gene silencing we determined the most probable routes of cellular uptake for each form of tested silica NPs. We observed differences in cellular uptake depending on the size and the agglomeration state of NPs. Caveolae-mediated endocytosis was implicated particularly in the internalisation of well dispersed silica NPs but with an increase of the agglomeration state of NPs a combination of endocytic pathways with a predominant role of macropinocytosis was noted. We demonstrated that the agglomeration state of NPs is an important factor influencing the level of cell uptake and the mechanism of endocytosis of silica NPs.

Effect of diesel exhaust generated by a city bus engine on stress responses and innate immunity in primary bronchial epithelial cell cultures.

PubMed

Zarcone, M C; Duistermaat, E; Alblas, M J; van Schadewijk, A; Ninaber, D K; Clarijs, V; Moerman, M M; Vaessen, D; Hiemstra, P S; Kooter, I M

2018-04-01

Harmful effects of diesel emissions can be investigated via exposures of human epithelial cells, but most of previous studies have largely focused on the use of diesel particles or emission sources that are poorly representative of engines used in current traffic. We studied the cellular response of primary bronchial epithelial cells (PBECs) at the air-liquid interface (ALI) to the exposure to whole diesel exhaust (DE) generated by a Euro V bus engine, followed by treatment with UV-inactivated non-typeable Haemophilus influenzae (NTHi) bacteria to mimic microbial exposure. The effect of prolonged exposures was investigated, as well as the difference in the responses of cells from COPD and control donors and the effect of emissions generated during a cold start. HMOX1 and NQO1 expression was transiently induced after DE exposure. DE inhibited the NTHi-induced expression of human beta-defensin-2 (DEFB4A) and of the chaperone HSPA5/BiP. In contrast, expression of the stress-induced PPP1R15A/GADD34 and the chemokine CXCL8 was increased in cells exposed to DE and NTHi. HMOX1 induction was significant in both COPD and controls, while inhibition of DEFB4A expression by DE was significant only in COPD cells. No significant differences were observed when comparing cellular responses to cold engine start and prewarmed engine emissions. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Effects of adrenalectomy on the alpha-adrenergic regulation of cytosolic free calcium in hepatocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Freudenrich, C.C.; Borle, A.B.

1988-06-25

We have previously published that bilateral adrenalectomy in the rat reduces the Ca2+-mediated alpha-adrenergic activation of hepatic glycogenolysis, while it increases the cellular calcium content of hepatocytes. In the experiments presented here, the concentration of cytosolic free calcium (Ca2+i) at rest and in response to epinephrine was measured in aequorin-loaded hepatocytes isolated from sham and adrenalectomized male rats. We found that in adrenalectomized rats the resting Ca2+i was elevated, the rise in Ca2+i evoked by epinephrine was reduced, and the rise in /sup 45/Ca efflux that follows such stimulation was depressed. Furthermore, the slope of the relationship between Ca2+i andmore » calcium efflux was decreased 60% in adrenalectomized. Adrenalectomy did not change Ca2+ release from intracellular calcium pools in response to IP3 in saponin-permeabilized hepatocytes. The EC50 for inositol 1,4,5-triphosphate and the maximal Ca2+ released were similar in both sham and adrenalectomized animals. Finally, the liver calmodulin content determined by radioimmunoassay was not significantly different between sham and adrenalectomized rats. These results suggest that 1) adrenalectomy reduces calcium efflux from the hepatocyte, probably by an effect on the plasma membrane (Ca2+-Mg2+)-ATPase-dependent Ca2+ pump and thus alters cellular calcium homeostasis; 2) adrenalectomy decreases the rise in Ca2+i in response to epinephrine; 3) this decreased rise in Ca2+i is not due to defects in the intracellular Ca2+ storage and mobilization processes; and 4) the effects of adrenalectomy on cellular calcium metabolism and on alpha-adrenergic activation of glycogenolysis are not caused by a reduction in soluble calmodulin.« less

Investigating the potential role of vitamin E in modulating the immunosuppressive effects of tylvalosin and florfenicol in broiler chickens.

PubMed

El-Ela, Fatma I Abo; Shany, S A S; El-Deen, Manal B; El-Banna, H A; El-Gendy, A A; Hendy, K; Tohamy, M A

2016-10-01

Tylvalosin (TVS) is a third-generation macrolide drug used for prophylaxis and treatment of mycoplasma, however; it is supposed to possess an immunosuppressive effect. In the current study, the immunosuppressive effect of TVS and florfenicol (FFC) and the potential immunomodulatory role of Vit E were investigated. The experiment included one day old chick groups treated with either TVS, FFC, Vit E, TVS/Vit E, FFC/Vit E and control non-treated group. Chicks were vaccinated with inactivated H9N2 avian influenza (AI) vaccine and humoral antibody titers to viral antigen as well as innate immunity (serum lysozyme activity and nitric oxide levels) were evaluated. Total and differential leucocytic counts, serum liver enzymes level, blood leucocytic DNA damage and cellular area percentages within the lymphoid organs were also screened. Treatment with TVS and FFC significantly decreased immune response of chickens while treatment with Vit E improved the humoral immune response at 4 and 5weeks post-vaccination. Vit E also significantly increased the cellular immune response. The combination of Vit E with either TVS or FFC modulated their immunosuppressive effect and resulted in mild immunostimulatory effects. TVS alone induced a genotoxic effect on chickens' blood leucocytes and the genotoxicity was inhibited by combination of TVS with Vit E. Histopathology revealed that chickens treated with either TVS or FFC exhibited toxic effect on the lymphatic tissues. Copyright © 2016 Elsevier Ltd. All rights reserved.

The actions of metabolic inhibition on human detrusor smooth muscle contractility from stable and unstable bladders.

PubMed

Hockey, J S; Wu, C; Fry, C H

2000-09-01

To determine the important cellular site(s) of action of a brief exposure to NaCN (chosen to reduce mitochondrial respiration and hence mimic cellular hypoxia) on the mechanical properties and regulation of intracellular [Ca2+] in human detrusor smooth muscle. Using muscle samples obtained from patients with stable and unstable bladders, to determine whether the unstable bladder is associated with changes in the functional properties of detrusor muscle under these circumstances. Materials and methods Experiments were conducted in vitro on muscle strips or isolated cells. Isometric tension was recorded in muscle strips during electrical stimulation or exposure to agonists. Intracellular [Ca2+] and [H+] were measured by epifluorescence microscopy, and cell autofluorescence measured as an index of mitochondrial function. There were no differences in the responses to electrical stimulation and varying concentrations of carbachol in muscle strips from stable and unstable bladders. NaCN (2 mmol/L) reduced the contraction induced by carbachol (10 micromol/L) by a mean (SD) of 43 (16)% and 56 (15)% in the two groups; the reduction in the unstable was significantly less than in the stable group. NaCN similarly reduced the response to 10 mmol/L caffeine, but had no effect on the KCl-induced contraction. NaCN significantly increased the resting sarcoplasmic [Ca2+] and attenuated the calcium transients evoked by carbachol and caffeine, but again had no effect on the KCl-induced transient. The reduction of the carbachol calcium transient was also less in cells from unstable bladders than in those from stable bladders. There was no effect of NaCN on intracellular pH, except for a brief, transient alkalosis. NaCN reduces both the contraction and Ca-transient to carbachol by reducing Ca2+ accumulation by intracellular stores, because the carbachol- and caffeine-evoked responses were similar. Any effect on transmembrane Ca2+ flux was minimal because there was no effect on KCl-induced responses. The greater resilience of tissue from unstable bladders to acute cellular hypoxia may reflect some adaptation acquired in vivo.

Altered cellular and humoral immunity to varicella-zoster virus in patients with autoimmune diseases.

PubMed

Rondaan, Christien; de Haan, Aalzen; Horst, Gerda; Hempel, J Cordelia; van Leer, Coretta; Bos, Nicolaas A; van Assen, Sander; Bijl, Marc; Westra, Johanna

2014-11-01

Patients with autoimmune diseases such as systemic lupus erythematosus (SLE) and granulomatosis with polyangiitis (Wegener's) (GPA) have a 3-20-fold increased risk of herpes zoster compared to the general population. The aim of this study was to evaluate if susceptibility is due to decreased levels of cellular and/or humoral immunity to the varicella-zoster virus (VZV). A cross-sectional study of VZV-specific immunity was performed in 38 SLE patients, 33 GPA patients, and 51 healthy controls. Levels of IgG and IgM antibodies to VZV were measured using an in-house glycoprotein enzyme-linked immunosorbent assay (ELISA). Cellular responses to VZV were determined by interferon-γ (IFNγ) enzyme-linked immunospot (ELISpot) assay and carboxyfluorescein succinimidyl ester (CFSE) dye dilution proliferation assay. Levels of IgG antibodies to VZV were increased in SLE patients as compared to healthy controls, but levels of IgM antibodies to VZV were not. Antibody levels in GPA patients did not differ significantly from levels in healthy controls. In response to stimulation with VZV, decreased numbers of IFNγ spot-forming cells were found among SLE patients (although not GPA patients) as compared to healthy controls. Proliferation of CD4+ T cells in response to stimulation with VZV was decreased in SLE patients but not GPA patients. SLE patients have increased levels of IgG antibodies against VZV, while cellular immunity is decreased. In GPA patients, antibody levels as well as cellular responses to VZV were comparable to those in healthy controls. These data suggest that increased prevalence of herpes zoster in SLE patients is due to a poor cellular response. Vaccination strategies should aim to boost cellular immunity against VZV. Copyright © 2014 by the American College of Rheumatology.

Evaluation of the health impact of aerosols emitted from different combustion sources: Comprehensive characterization of the aerosol physicochemical properties as well as the molecular biological and toxicological effects of the aerosols on human lung cells and macrophages.

NASA Astrophysics Data System (ADS)

Zimmermann, R.; Dittmar, G.; Kanashova, T.; Buters, J.; Öder, S.; Paur, H. R.; Mülhopt, S.; Dilger, M.; Weiss, C.; Harndorf, H.; Stengel, B.; Hirvonen, M. R.; Jokiniemi, J.; Hiller, K.; Sapcariu, S.; Sippula, O.; Streibel, T.; Karg, E.; Weggler, B.; Schnelle-Kreis, J.; Lintelmann, J.; Sklorz, M.; Orasche, J.; Müller, L.; Passig, J.; Gröger, T.; Jalava, P. I.; Happo, M.; Uski, O.

2016-12-01

A novel approach to evaluate the health effects of anthropogenic combustion emissions is the detailed comparison of comprehensive physicochemical data on the combustion aerosol properties with the biological response of aerosol-exposed lung cells. In this context the "HICE-Aerosol and Health" project consortium studies the properties as well as the biological and toxicological effects on lung cells induced by different combustion aerosol emissions (e.g. ship diesel exhaust, wood combustion effluents or automobile aerosol). Human alveolar epithelial cells (e.g. A549 cells) as well as murine macrophages were exposed to diluted emissions, using field deployable ALI-exposition systems in a mobile S2-biological laboratory. This allows a realistic lung-cell exposure by simulation of the lung situation. The cellular effects were then comprehensively characterized (cytotoxicology, transcriptomics, proteomics etc.) effects monitoring and put in context with the chemical and physical aerosol data. Emissions of wood combustion, a ship engine as well as diesel and gasoline engines were investigated. Furthermore for some experiments the atmospheric aging of the emission was simulated in a flow tube reactor using UV-light and ozone. Briefly the following order of cellular response-strength was observed: A relatively mild cellular effect is observed for the diluted wood combustion emissions, regardless if log-wood and pellet burner emissions are investigated. Similarly mild biological effects are observed for gasoline car emissions. The ship diesel engine emissions and construction machine diesel engine induced much more intense biological responses. A surprising result in this context is, that heavy fuel oil (HFO)-emissions show lower biological effect strengths than the supposedly cleaner diesel fuel emissions (DF). The HFO-emissions contain high concentrations of known toxicants (metals, polycyclic aromatics). This result was confirmed by experiments with murine macrophages. Detailed analyses suggest a large difference in relative toxicity for different combustion sources. Recently the cell experiments were successively evaluated and verified by animal exposure tests. This is important to develop a reliable animal-test free-monitoring method for aerosol-induced health effects.

Evaluation of the health impact of aerosols emitted from different combustion sources: Comprehensive characterization of the aerosol physicochemical properties as well as the molecular biological and toxicological effects of the aerosols on human lung cells and macrophages.

NASA Astrophysics Data System (ADS)

Zimmermann, R.; Dittmar, G.; Kanashova, T.; Buters, J.; Öder, S.; Paur, H. R.; Mülhopt, S.; Dilger, M.; Weiss, C.; Harndorf, H.; Stengel, B.; Hirvonen, M. R.; Jokiniemi, J.; Hiller, K.; Sapcariu, S.; Sippula, O.; Streibel, T.; Karg, E.; Weggler, B.; Schnelle-Kreis, J.; Lintelmann, J.; Sklorz, M.; Orasche, J.; Müller, L.; Passig, J.; Gröger, T.; Jalava, P. I.; Happo, M.; Uski, O.

2017-12-01

A novel approach to evaluate the health effects of anthropogenic combustion emissions is the detailed comparison of comprehensive physicochemical data on the combustion aerosol properties with the biological response of aerosol-exposed lung cells. In this context the "HICE-Aerosol and Health" project consortium studies the properties as well as the biological and toxicological effects on lung cells induced by different combustion aerosol emissions (e.g. ship diesel exhaust, wood combustion effluents or automobile aerosol). Human alveolar epithelial cells (e.g. A549 cells) as well as murine macrophages were exposed to diluted emissions, using field deployable ALI-exposition systems in a mobile S2-biological laboratory. This allows a realistic lung-cell exposure by simulation of the lung situation. The cellular effects were then comprehensively characterized (cytotoxicology, transcriptomics, proteomics etc.) effects monitoring and put in context with the chemical and physical aerosol data. Emissions of wood combustion, a ship engine as well as diesel and gasoline engines were investigated. Furthermore for some experiments the atmospheric aging of the emission was simulated in a flow tube reactor using UV-light and ozone. Briefly the following order of cellular response-strength was observed: A relatively mild cellular effect is observed for the diluted wood combustion emissions, regardless if log-wood and pellet burner emissions are investigated. Similarly mild biological effects are observed for gasoline car emissions. The ship diesel engine emissions and construction machine diesel engine induced much more intense biological responses. A surprising result in this context is, that heavy fuel oil (HFO)-emissions show lower biological effect strengths than the supposedly cleaner diesel fuel emissions (DF). The HFO-emissions contain high concentrations of known toxicants (metals, polycyclic aromatics). This result was confirmed by experiments with murine macrophages. Detailed analyses suggest a large difference in relative toxicity for different combustion sources. Recently the cell experiments were successively evaluated and verified by animal exposure tests. This is important to develop a reliable animal-test free-monitoring method for aerosol-induced health effects.

Nuclear Cytoplasmic Trafficking of Proteins is a Major Response of Human Fibroblasts to Oxidative Stress

PubMed Central

Baqader, Noor O.; Radulovic, Marko; Crawford, Mark; Stoeber, Kai; Godovac-Zimmermann, Jasminka

2014-01-01

We have used a subcellular spatial razor approach based on LC–MS/MS-based proteomics with SILAC isotope labeling to determine changes in protein abundances in the nuclear and cytoplasmic compartments of human IMR90 fibroblasts subjected to mild oxidative stress. We show that response to mild tert-butyl hydrogen peroxide treatment includes redistribution between the nucleus and cytoplasm of numerous proteins not previously associated with oxidative stress. The 121 proteins with the most significant changes encompass proteins with known functions in a wide variety of subcellular locations and of cellular functional processes (transcription, signal transduction, autophagy, iron metabolism, TCA cycle, ATP synthesis) and are consistent with functional networks that are spatially dispersed across the cell. Both nuclear respiratory factor 2 and the proline regulatory axis appear to contribute to the cellular metabolic response. Proteins involved in iron metabolism or with iron/heme as a cofactor as well as mitochondrial proteins are prominent in the response. Evidence suggesting that nuclear import/export and vesicle-mediated protein transport contribute to the cellular response was obtained. We suggest that measurements of global changes in total cellular protein abundances need to be complemented with measurements of the dynamic subcellular spatial redistribution of proteins to obtain comprehensive pictures of cellular function. PMID:25133973

Micromechanics of Amorphous Metal/Polymer Hybrid Structures with 3D Cellular Architectures: Size Effects, Buckling Behavior, and Energy Absorption Capability.

PubMed

Mieszala, Maxime; Hasegawa, Madoka; Guillonneau, Gaylord; Bauer, Jens; Raghavan, Rejin; Frantz, Cédric; Kraft, Oliver; Mischler, Stefano; Michler, Johann; Philippe, Laetitia

2017-02-01

By designing advantageous cellular geometries and combining the material size effects at the nanometer scale, lightweight hybrid microarchitectured materials with tailored structural properties are achieved. Prior studies reported the mechanical properties of high strength cellular ceramic composites, obtained by atomic layer deposition. However, few studies have examined the properties of similar structures with metal coatings. To determine the mechanical performance of polymer cellular structures reinforced with a metal coating, 3D laser lithography and electroless deposition of an amorphous layer of nickel-boron (NiB) is used for the first time to produce metal/polymer hybrid structures. In this work, the mechanical response of microarchitectured structures is investigated with an emphasis on the effects of the architecture and the amorphous NiB thickness on their deformation mechanisms and energy absorption capability. Microcompression experiments show an enhancement of the mechanical properties with the NiB thickness, suggesting that the deformation mechanism and the buckling behavior are controlled by the brittle-to-ductile transition in the NiB layer. In addition, the energy absorption properties demonstrate the possibility of tuning the energy absorption efficiency with adequate designs. These findings suggest that microarchitectured metal/polymer hybrid structures are effective in producing materials with unique property combinations. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

[Immune response to live influenza vaccine].

PubMed

Naĭkhin, A N; Rekstin, A R; Barantseva, I B; Donina, S A; Desheva, Iu A; Grigor'eva, E P; Kiseleva, I V; Rudenko, L G

2002-01-01

Priority data on the induction, by using a Russian live cold-adapted reassortant influenza vaccine (LIV), of the cellular and humoral immunity with regard for attenuation and genetic reassortment of vaccine stains as well as with regard for the age of vaccinated persons and the production of Th1 (IFNY, IL-2) and Th2 (IL-4) cytokine markers in vitro are presented. It was demonstrated in vivo that a pathogenic virus of the A group by far more actively induced the lymphocyte apoptosis as compared with attenuated genetically reassorted stains. Unlike the influenza pathogenic virus, the genetically attenuated and reassorted strain did not produce any negative effects on the induction of cellular immunity. A comparative study of the LIV immunogenic properties in vaccinated persons showed an advantage of LIV over inactivated influenza vaccine (IIV) in stimulating the cellular and local immunity in the elderly. Unlike IIV, LIV induced an active and balanced immune response developing due to Th1 and Th2 activation. LIV was found to stimulate well enough the production of IFN and IL-2 in both young and old persons.

Parasitism and venom of ectoparasitoid Scleroderma guani impairs host cellular immunity.

PubMed

Li, Li-Fang; Xu, Zhi-Wen; Liu, Nai-Yong; Wu, Guo-Xing; Ren, Xue-Min; Zhu, Jia-Ying

2018-06-01

Venom is a prominently maternal virulent factor utilized by parasitoids to overcome hosts immune defense. With respect to roles of this toxic mixture involved in manipulating hosts immunity, great interest has been mostly restricted to Ichneumonoidea parasitoids associated with polydnavirus (PDV), of which venom is usually considered as a helper component to enhance the role of PDV, and limited Chalcidoidea species. In contrast, little information is available in other parasitoids, especially ectoparasitic species not carrying PDV. The ectoparasitoid Scleroderma guani injects venom into its host, Tenebrio molitor, implying its venom was involved in suppression of hosts immune response for successful parasitism. Thus, we investigated the effects of parasitism and venom of this parasitoid on counteracting the cellular immunity of its host by examining changes of hemocyte counts, and hemocyte spreading and encapsulation ability. Total hemocyte counts were elevated in parasitized and venom-injected pupae. The spreading behavior of both granulocytes and plasmatocytes was impaired by parasitization and venom. High concentration of venom led to more severely increased hemocyte counts and suppression of hemocyte spreading. The ability of hemocyte encapsulation was inhibited by venom in vitro. In addition to immediate effects observed, venom showed persistent interference in hosts cellular immunity. These results indicate that venom alone from S. guani plays a pivotal role in blocking hosts cellular immune response, serving as a regulator that guarantees the successful development of its progenies. The findings provide a foundation for further investigation of the underlying mechanisms in immune inhibitory action of S. guani venom. © 2018 Wiley Periodicals, Inc.

Effects of Simulated Microgravity on Functions of Neutrophil-like HL-60 Cells

NASA Astrophysics Data System (ADS)

Wang, Chengzhi; Li, Ning; Zhang, Chen; Sun, Shujin; Gao, Yuxin; Long, Mian

2015-11-01

Altered gravity, especially microgravity affects cellular functions of immune cells and can result in immune dysfunction for long-term, manned spaceflight and space exploration. The underlying mechanism, however, of sensing and responding to the gravity alteration is poorly understood. Here, a rotary cell culture system (RCCS) bioreactor was used to elucidate the effects of simulated microgravity on polymorphonuclear neutrophils (PMN)-like HL-60 cells. Alteration of cell morphology, up-regulation of (nitric oxide) NO production, enhancement of interleukin-6 (IL-6), interleukin-8 (IL-8), and monocyte chemotactic protein 1 (MCP-1) secretion, and diversity of cellular adhesion molecule expression were observed for the cells cultured in RCCS, leading to the up-regulated inflammatory immune responses and host defense. It was also indicated that such alterations in biological responses of PMNs mediated the reduced rolling velocity and decreased adhesion of PMN-like HL-60 cells on endothelial cells under shear flow. This work furthers the understandings in the effects and mechanism of microgravity on PMN functions, which are potentially helpful for optimizing the countermeasures to immune suppression in the future long-term, manned spaceflight.

Deep-brain magnetic stimulation promotes adult hippocampal neurogenesis and alleviates stress-related behaviors in mouse models for neuropsychiatric disorders

PubMed Central

2014-01-01

Background Repetitive Transcranial Magnetic Stimulation (rTMS)/ Deep-brain Magnetic Stimulation (DMS) is an effective therapy for various neuropsychiatric disorders including major depression disorder. The molecular and cellular mechanisms underlying the impacts of rTMS/DMS on the brain are not yet fully understood. Results Here we studied the effects of deep-brain magnetic stimulation to brain on the molecular and cellular level. We examined the adult hippocampal neurogenesis and hippocampal synaptic plasticity of rodent under stress conditions with deep-brain magnetic stimulation treatment. We found that DMS promotes adult hippocampal neurogenesis significantly and facilitates the development of adult new-born neurons. Remarkably, DMS exerts anti-depression effects in the learned helplessness mouse model and rescues hippocampal long-term plasticity impaired by restraint stress in rats. Moreover, DMS alleviates the stress response in a mouse model for Rett syndrome and prolongs the life span of these animals dramatically. Conclusions Deep-brain magnetic stimulation greatly facilitates adult hippocampal neurogenesis and maturation, also alleviates depression and stress-related responses in animal models. PMID:24512669

Metabolic gene regulation in a dynamically changing environment.

PubMed

Bennett, Matthew R; Pang, Wyming Lee; Ostroff, Natalie A; Baumgartner, Bridget L; Nayak, Sujata; Tsimring, Lev S; Hasty, Jeff

2008-08-28

Natural selection dictates that cells constantly adapt to dynamically changing environments in a context-dependent manner. Gene-regulatory networks often mediate the cellular response to perturbation, and an understanding of cellular adaptation will require experimental approaches aimed at subjecting cells to a dynamic environment that mimics their natural habitat. Here we monitor the response of Saccharomyces cerevisiae metabolic gene regulation to periodic changes in the external carbon source by using a microfluidic platform that allows precise, dynamic control over environmental conditions. We show that the metabolic system acts as a low-pass filter that reliably responds to a slowly changing environment, while effectively ignoring fast fluctuations. The sensitive low-frequency response was significantly faster than in predictions arising from our computational modelling, and this discrepancy was resolved by the discovery that two key galactose transcripts possess half-lives that depend on the carbon source. Finally, to explore how induction characteristics affect frequency response, we compare two S. cerevisiae strains and show that they have the same frequency response despite having markedly different induction properties. This suggests that although certain characteristics of the complex networks may differ when probed in a static environment, the system has been optimized for a robust response to a dynamically changing environment.

Ionic Control of the Reversal Response of Cilia in Paramecium caudatum

PubMed Central

Naitoh, Yutaka

1968-01-01

The duration of ciliary reversal of Paramecium caudatum in response to changes in external ionic factors was determined with various ionic compositions of both equilibration and stimulation media. The reversal response was found to occur when calcium ions bound by an inferred cellular cation exchange system were liberated in exchange for externally applied cations other than calcium. Factors which affect the duration of the response were (a) initial amount of calcium bound by the cation exchange system, (b) final amount of calcium bound by the system after equilibration with the stimulation medium, and (c) concentration of calcium ions in the stimulation medium. An empirical equation is presented which relates the duration of the response to these three factors. On the basis of these and previously published data, the following hypothesis is proposed for the mechanism underlying ciliary reversal in response to cationic stimulation: Ca++ liberated from the cellular cation exchange system activates a contractile system which is energized by ATP. Contraction of this component results in the reversal of effective beat direction of cilia by a mechanism not yet understood. The duration of reversal in live paramecia is related to the time course of bound calcium release. PMID:4966766

Measuring Cellular Immunity to Influenza: Methods of Detection, Applications and Challenges

PubMed Central

Coughlan, Lynda; Lambe, Teresa

2015-01-01

Influenza A virus is a respiratory pathogen which causes both seasonal epidemics and occasional pandemics; infection continues to be a significant cause of mortality worldwide. Current influenza vaccines principally stimulate humoral immune responses that are largely directed towards the variant surface antigens of influenza. Vaccination can result in an effective, albeit strain-specific antibody response and there is a need for vaccines that can provide superior, long-lasting immunity to influenza. Vaccination approaches targeting conserved viral antigens have the potential to provide broadly cross-reactive, heterosubtypic immunity to diverse influenza viruses. However, the field lacks consensus on the correlates of protection for cellular immunity in reducing severe influenza infection, transmission or disease outcome. Furthermore, unlike serological methods such as the standardized haemagglutination inhibition assay, there remains a large degree of variation in both the types of assays and method of reporting cellular outputs. T-cell directed immunity has long been known to play a role in ameliorating the severity and/or duration of influenza infection, but the precise phenotype, magnitude and longevity of the requisite protective response is unclear. In order to progress the development of universal influenza vaccines, it is critical to standardize assays across sites to facilitate direct comparisons between clinical trials. PMID:26343189

Molecular and cellular profiling of acute responses to total body radiation exposure in ovariectomized female cynomolgus macaques.

PubMed

DeBo, Ryne J; Register, Thomas C; Caudell, David L; Sempowski, Gregory D; Dugan, Gregory; Gray, Shauna; Owzar, Kouros; Jiang, Chen; Bourland, J Daniel; Chao, Nelson J; Cline, J Mark

2015-06-01

The threat of radiation exposure requires a mechanistic understanding of radiation-induced immune injury and recovery. The study objective was to evaluate responses to ionizing radiation in ovariectomized (surgically post-menopausal) female cynomolgus macaques. Animals received a single total-body irradiation (TBI) exposure at doses of 0, 2 or 5 Gy with scheduled necropsies at 5 days, 8 weeks and 24 weeks post-exposure. Blood and lymphoid tissues were evaluated for morphologic, cellular, and molecular responses. Irradiated animals developed symptoms of acute hematopoietic syndrome, and reductions in thymus weight, thymopoiesis, and bone marrow cellularity. Acute, transient increases in plasma monocyte chemoattractant protein 1 (MCP-1) were observed in 5 Gy animals along with dose-dependent alterations in messenger ribonucleic acid (mRNA) signatures in thymus, spleen, and lymph node. Expression of T cell markers was lower in thymus and spleen, while expression of macrophage marker CD68 (cluster of differentiation 68) was relatively elevated in lymphoid tissues from irradiated animals. Ovariectomized female macaques exposed to moderate doses of radiation experienced increased morbidity, including acute, dose-dependent alterations in systemic and tissue-specific biomarkers, and increased macrophage/T cell ratios. The effects on mortality exceeded expectations based on previous studies in males, warranting further investigation.

Cellular responses to environmental DNA damage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

This volume contains the proceedings of the conference entitled Cellular Responses to Environmental DNA Damage held in Banff,Alberta December 1--6, 1991. The conference addresses various aspects of DNA repair in sessions titled DNA repair; Basic Mechanisms; Lesions; Systems; Inducible Responses; Mutagenesis; Human Population Response Heterogeneity; Intragenomic DNA Repair Heterogeneity; DNA Repair Gene Cloning; Aging; Human Genetic Disease; and Carcinogenesis. Individual papers are represented as abstracts of about one page in length.

Hepatitis C Virus Infection Induces Autophagy as a Prosurvival Mechanism to Alleviate Hepatic ER-Stress Response

PubMed Central

Dash, Srikanta; Chava, Srinivas; Aydin, Yucel; Chandra, Partha K.; Ferraris, Pauline; Chen, Weina; Balart, Luis A.; Wu, Tong; Garry, Robert F.

2016-01-01

Hepatitis C virus (HCV) infection frequently leads to chronic liver disease, liver cirrhosis and hepatocellular carcinoma (HCC). The molecular mechanisms by which HCV infection leads to chronic liver disease and HCC are not well understood. The infection cycle of HCV is initiated by the attachment and entry of virus particles into a hepatocyte. Replication of the HCV genome inside hepatocytes leads to accumulation of large amounts of viral proteins and RNA replication intermediates in the endoplasmic reticulum (ER), resulting in production of thousands of new virus particles. HCV-infected hepatocytes mount a substantial stress response. How the infected hepatocyte integrates the viral-induced stress response with chronic infection is unknown. The unfolded protein response (UPR), an ER-associated cellular transcriptional response, is activated in HCV infected hepatocytes. Over the past several years, research performed by a number of laboratories, including ours, has shown that HCV induced UPR robustly activates autophagy to sustain viral replication in the infected hepatocyte. Induction of the cellular autophagy response is required to improve survival of infected cells by inhibition of cellular apoptosis. The autophagy response also inhibits the cellular innate antiviral program that usually inhibits HCV replication. In this review, we discuss the physiological implications of the HCV-induced chronic ER-stress response in the liver disease progression. PMID:27223299

HOMEOTHERMY: DOES IT IMPEDE THE RESPONSE TO CELLULAR INJURY

EPA Science Inventory

Homeostasis of core temperature is considered to be one of the most precise regulatory processes. n this paper it is postulated that homeothermy is so effective, especially in species of-relatively large mass (including humans), that it limits the ability to survive ischemia, tox...

Effect of MPS1 Inhibition on Genotoxic Stress Responses in Murine Tumour Cells.

PubMed

Suzuki, Motofumi; Yamamori, Tohru; Yasui, Hironobu; Inanami, Osamu

2016-06-01

The monopolar spindle 1 (MPS1) is a serine/threonine kinase that plays an important role in spindle assembly checkpoint signaling. To determine the possible relationship between MPS1 inhibition and genotoxic stress responses, herein we examined whether MPS1 inhibition influences cellular susceptibility towards two genotoxic treatments, etoposide and ionizing radiation (IR). Two murine tumour cell lines, SCCVII and EMT6, were used. The effect of genotoxic treatments with or without two novel MPS1 inhibitors, NMS-P715 and AZ3146, on cellular survival, cell-cycle distribution, centrosome status and mitotic catastrophe (MC) was evaluated. MPS1 inhibition sensitized murine tumour cells to etoposide but not to IR. In addition, MPS1 inhibition altered cell-cycle progression and exacerbated centrosome abnormalities, resulting in enhanced MC induced by etoposide but not by IR. MPS1 inhibition promotes the etoposide-induced aberrant mitosis and, consequently, the induction of tumour cell death. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Chamomile confers protection against hydrogen peroxide-induced toxicity through activation of Nrf2-mediated defense response.

PubMed

Bhaskaran, Natarajan; Srivastava, Janmejai K; Shukla, Sanjeev; Gupta, Sanjay

2013-01-01

Oxidative stress plays an important role in the development of various human diseases. Aqueous chamomile extract is used as herbal medicine, in the form of tea, demonstrated to possess antiinflammatory and antioxidant properties. We demonstrate the cytoprotective effects of chamomile on hydrogen peroxide (H₂O₂)-induced cellular damage in macrophage RAW 264.7 cells. Pretreatment of cells with chamomile markedly attenuated H₂O₂-induced cell viability loss in a dose-dependent manner. The mechanisms by which chamomile-protected macrophages from oxidative stress was through the induction of several antioxidant enzymes including NAD(P)H:quinone oxidoreductase, superoxide dismutase, and catalase and increase nuclear accumulation of the transcription factor Nrf2 and its binding to antioxidant response elements. Furthermore, chamomile dose-dependently reduced H₂O₂-mediated increase in the intracellular levels of reactive oxygen species. Our results, for the first time, demonstrate that chamomile has protective effects against oxidative stress and might be beneficial to provide defense against cellular damage. Copyright © 2012 John Wiley & Sons, Ltd.

Chamomile Confers Protection against Hydrogen Peroxide-Induced Toxicity through Activation of Nrf2-Mediated Defense Response

PubMed Central

Bhaskaran, Natarajan; Srivastava, Janmejai K.; Shukla, Sanjeev; Gupta, Sanjay

2014-01-01

Oxidative stress plays an important role in the development of various human diseases. Aqueous chamomile extract is used as herbal medicine, in the form of tea, demonstrated to possess antiinflammatory and antioxidant properties. We demonstrate the cytoprotective effects of chamomile on hydrogen peroxide (H2O2)-induced cellular damage in macrophage RAW 264.7 cells. Pretreatment of cells with chamomile markedly attenuated H2O2-induced cell viability loss in a dose-dependent manner. The mechanisms by which chamomile-protected macrophages from oxidative stress was through the induction of several antioxidant enzymes including NAD (P)H:quinone oxidoreductase, superoxide dismutase, and catalase and increase nuclear accumulation of the transcription factor Nrf2 and its binding to antioxidant response elements. Furthermore, chamomile dose-dependently reduced H2O2-mediated increase in the intracellular levels of reactive oxygen species. Our results, for the first time, demonstrate that chamomile has protective effects against oxidative stress and might be beneficial to provide defense against cellular damage. PMID:22511316

Evaluation of immunomodulatory activity of methanolic extract of Piper betel.

PubMed

Kanjwani, D G; Marathe, T P; Chiplunkar, S V; Sathaye, S S

2008-06-01

Many of the disorders today are based on the imbalances of immunological processes. This necessitates the search for newer and safer immunomodulators. Thus, the objective of the present study was to explore the immunomodulatory activity of the methanolic extract of Piper betel L. (MPb) (Family: Piperaceae). The MPb consists of mixture of phenols, flavonoids, tannins and polysaccharides. Both in vitro as well as in vivo evaluation was carried out. The effects of MPb on lymphocyte proliferation, interferon-gamma receptors and the production of nitric oxide were measured in vitro. Further, the extract at different dose levels was studied in vivo for the humoral and cellular immune responses on mice immunized with sheep red blood cells. P. betel significantly suppressed phytohaemagglutinin stimulated peripheral blood lymphocyte proliferation in a dose-dependent manner. The decrease in antibody titre and increased suppression of inflammation suggests possible immunosuppressive effect of extract on cellular and humoral response in mice. Thus, the MPb could be explored extensively as a therapeutic agent to treat various immune disorders including autoimmune disorders.

Role of cellular adhesions in tissue dynamics spectroscopy

NASA Astrophysics Data System (ADS)

Merrill, Daniel A.; An, Ran; Turek, John; Nolte, David

2014-02-01

Cellular adhesions play a critical role in cell behavior, and modified expression of cellular adhesion compounds has been linked to various cancers. We tested the role of cellular adhesions in drug response by studying three cellular culture models: three-dimensional tumor spheroids with well-developed cellular adhesions and extracellular matrix (ECM), dense three-dimensional cell pellets with moderate numbers of adhesions, and dilute three-dimensional cell suspensions in agarose having few adhesions. Our technique for measuring the drug response for the spheroids and cell pellets was biodynamic imaging (BDI), and for the suspensions was quasi-elastic light scattering (QELS). We tested several cytoskeletal chemotherapeutic drugs (nocodazole, cytochalasin-D, paclitaxel, and colchicine) on three cancer cell lines chosen from human colorectal adenocarcinoma (HT-29), human pancreatic carcinoma (MIA PaCa-2), and rat osteosarcoma (UMR-106) to exhibit differences in adhesion strength. Comparing tumor spheroid behavior to that of cell suspensions showed shifts in the spectral motion of the cancer tissues that match predictions based on different degrees of cell-cell contacts. The HT-29 cell line, which has the strongest adhesions in the spheroid model, exhibits anomalous behavior in some cases. These results highlight the importance of using three-dimensional tissue models in drug screening with cellular adhesions being a contributory factor in phenotypic differences between the drug responses of tissue and cells.

The Effects of Airway Microbiome on Corticosteroid Responsiveness in Asthma

PubMed Central

Goleva, Elena; Jackson, Leisa P.; Harris, J. Kirk; Robertson, Charles E.; Sutherland, E. Rand; Hall, Clifton F.; Good, James T.; Gelfand, Erwin W.; Martin, Richard J.

2013-01-01

Rationale: The role of airway microbiome in corticosteroid response in asthma is unknown. Objectives: To examine airway microbiome composition in patients with corticosteroid-resistant (CR) asthma and compare it with patients with corticosteroid-sensitive (CS) asthma and normal control subjects and explore whether bacteria in the airways of subjects with asthma may direct alterations in cellular responses to corticosteroids. Methods: 16S rRNA gene sequencing was performed on bronchoalveolar lavage (BAL) samples of 39 subjects with asthma and 12 healthy control subjects. In subjects with asthma, corticosteroid responsiveness was characterized, BAL macrophages were stimulated with pathogenic versus commensal microorganisms, and analyzed by real-time polymerase chain reaction for the expression of corticosteroid-regulated genes and cellular p38 mitogen-activated protein kinase (MAPK) activation. Measurements and Main Results: Of the 39 subjects with asthma, 29 were CR and 10 were CS. BAL microbiome from subjects with CR and CS asthma did not differ in richness, evenness, diversity, and community composition at the phylum level, but did differ at the genus level, with distinct genus expansions in 14 subjects with CR asthma. Preincubation of asthmatic airway macrophages with Haemophilus parainfluenzae, a uniquely expanded potential pathogen found only in CR asthma airways, resulted in p38 MAPK activation, increased IL-8 (P < 0.01), mitogen-activated kinase phosphatase 1 mRNA (P < 0.01) expression, and inhibition of corticosteroid responses (P < 0.05). This was not observed after exposure to commensal bacterium Prevotella melaninogenica. Inhibition of transforming growth factor-β–associated kinase-1 (TAK1), upstream activator of MAPK, but not p38 MAPK restored cellular sensitivity to corticosteroids. Conclusions: A subset of subjects with CR asthma demonstrates airway expansion of specific gram-negative bacteria, which trigger TAK1/MAPK activation and induce corticosteroid resistance. TAK1 inhibition restored cellular sensitivity to corticosteroids. PMID:24024497

Emiliania huxleyi endures N-limitation with an efficient metabolic budgeting and effective ATP synthesis.

PubMed

Rokitta, Sebastian D; Von Dassow, Peter; Rost, Björn; John, Uwe

2014-12-02

Global change will affect patterns of nutrient upwelling in marine environments, potentially becoming even stricter regulators of phytoplankton primary productivity. To better understand phytoplankton nutrient utilization on the subcellular basis, we assessed the transcriptomic responses of the life-cycle stages of the biogeochemically important microalgae Emiliania huxleyi to nitrogen-limitation. Cells grown in batch cultures were harvested at 'early' and 'full' nitrogen-limitation and were compared with non-limited cells. We applied microarray-based transcriptome profilings, covering ~10.000 known E. huxleyi gene models, and screened for expression patterns that indicate the subcellular responses. The diploid life-cycle stage scavenges nitrogen from external organic sources and -like diatoms- uses the ornithine-urea cycle to rapidly turn over cellular nitrogen. The haploid stage reacts similarly, although nitrogen scavenging is less pronounced and lipid oxidation is more prominent. Generally, polyamines and proline appear to constitute major organic pools that back up cellular nitrogen. Both stages induce a malate:quinone-oxidoreductase that efficiently feeds electrons into the respiratory chain and drives ATP generation with reduced respiratory carbon throughput. The use of the ornithine-urea cycle to budget the cellular nitrogen in situations of limitation resembles the responses observed earlier in diatoms. This suggests that underlying biochemical mechanisms are conserved among distant clades of marine phototrophic protists. The ornithine-urea cycle and proline oxidation appear to constitute a sensory-regulatory system that monitors and controls cellular nitrogen budgets under limitation. The similarity between the responses of the life-cycle stages, despite the usage of different genes, also indicates a strong functional consistency in the responses to nitrogen-limitation that appears to be owed to biochemical requirements. The malate:quinone-oxidoreductase is a genomic feature that appears to be absent from diatom genomes, and it is likely to strongly contribute to the uniquely high endurance of E. huxleyi under nutrient limitation.

Immunomodulatory and cellular anti-oxidant activities of caffeic, ferulic, and p-coumaric phenolic acids: a structure-activity relationship study.

PubMed

Kilani-Jaziri, Soumaya; Mokdad-Bzeouich, Imen; Krifa, Mounira; Nasr, Nouha; Ghedira, Kamel; Chekir-Ghedira, Leila

2017-10-01

Many studies have been performed to assess the potential utility of natural products as immunomodulatory agents to enhance host responses and to reduce damage to the human body. To determine whether phenolic compounds (caffeic, ferulic, and p-coumaric acids) have immunomodulatory effects and clarify which types of immune effector cells are stimulated in vitro, we evaluated their effect on splenocyte proliferation and lysosomal enzyme activity. We also investigated the activity of natural killer (NK) cells and cytotoxic T lymphocytes (CTL). In addition, induction of the cellular antioxidant activity in splenocytes, macrophages, and red blood cells was determined by measuring the fluorescence of the DCF product. The study first results indicated that caffeic, ferulic, and p-coumaric acids significantly promote LPS-stimulated splenocyte proliferation, suggesting a potential activation of B cells, and enhanced humoral immune response in hosts treated by the tested natural products. Phenolic acids significantly enhanced the killing activity of isolated NK and CTL cells but had negligible effects on mitogen-induced proliferation of splenic T cells. We showed that caffeic acid enhances lysosomal enzyme activity in murine peritoneal macrophages, suggesting a potential role in activating such cells. Immunomodulatory activity was concomitant with the cellular antioxidant effect in macrophages and splenocytes of caffeic and ferulic acids. We conclude from this study that caffeic, ferulic, and p-coumaric acids exhibited an immunomodulatory effect which could be ascribed, in part, to their cytoprotective effect via their antioxidant capacity. Furthermore, these results suggest that these natural products could be potentially used to modulate immune cell functions in physiological and pathological conditions.

A comparison of serotonin neuromodulation of mouse spinal V2a interneurons using perforated patch and whole cell recording techniques

PubMed Central

Dietz, Shelby; Husch, Andreas; Harris-Warrick, Ronald M.

2012-01-01

Whole cell recordings (WCRs) are frequently used to study neuronal properties, but may be problematic when studying neuromodulatory responses, due to dialysis of the cell's cytoplasm. Perforated patch recordings (PPR) avoid cellular dialysis and might reveal additional modulatory effects that are lost during WCR. We have previously used WCR to characterize the responses of the V2a class of Chx10-expressing neurons to serotonin (5-HT) in the neonatal mouse spinal cord (Zhong et al., 2010). Here we directly compare multiple aspects of the responses to 5-HT using WCR and PPR in Chx10-eCFP neurons in spinal cord slices from 2 to 4 day old mice. Cellular properties recorded in PPR and WCR were similar, but high-quality PP recordings could be maintained for significantly longer. Both WCR and PPR cells could respond to 5-HT, and although neurons recorded by PPR showed a significantly greater response to 5-HT in some parameters, the absolute differences between PPR and WCR were small. We conclude that WCR is an acceptable recording method for short-term recordings of neuromodulatory effects, but the less invasive PPR is preferable for detailed analyses and is necessary for stable recordings lasting an hour or more. PMID:23060747

6.0 K microarray reveals differential transcriptomic responses in the dinoflagellate Prorocentrum minimum exposed to polychlorinated biphenyl (PCB).

PubMed

Wang, Hui; Guo, Ruoyu; Ki, Jang-Seu

2018-03-01

Endocrine disrupting chemicals (EDCs) have toxic effects on algae; however, their molecular genomic responses have not been sufficiently elucidated. Here, we evaluated genome-scaled responses of the dinoflagellate alga Prorocentrum minimum exposed to an EDC, polychlorinated biphenyl (PCB), using a 6.0 K microarray. Based on two-fold change cut-off, we identified that 609 genes (∼10.2%) responded to the PCB treatment. KEGG pathway analysis showed that differentially expressed genes (DEGs) were related to ribosomes, biosynthesis of amino acids, spliceosomes, and cellular processes. Many DEGs were involved in cell cycle progression, apoptosis, signal transduction, ion binding, and cellular transportation. In contrast, only a few genes related to photosynthesis and oxidative stress were expressed in response to PCB exposure. This was supported by that fact that there were no obvious changes in the photosynthetic efficiency and reactive oxygen species (ROS) production. These results suggest that PCB might not cause chloroplast and oxidative damage, but could lead to cell cycle arrest and apoptosis. In addition, various signal transduction and transport pathways might be disrupted in the cells, which could further contribute to cell death. These results expand the genomic understanding of the effects of EDCs on this dinoflagellate protist. Copyright © 2017 Elsevier Ltd. All rights reserved.

Neuroendocrine mechanisms for immune system regulation during stress in fish.

PubMed

Nardocci, Gino; Navarro, Cristina; Cortés, Paula P; Imarai, Mónica; Montoya, Margarita; Valenzuela, Beatriz; Jara, Pablo; Acuña-Castillo, Claudio; Fernández, Ricardo

2014-10-01

In the last years, the aquaculture crops have experienced an explosive and intensive growth, because of the high demand for protein. This growth has increased fish susceptibility to diseases and subsequent death. The constant biotic and abiotic changes experienced by fish species in culture are challenges that induce physiological, endocrine and immunological responses. These changes mitigate stress effects at the cellular level to maintain homeostasis. The effects of stress on the immune system have been studied for many years. While acute stress can have beneficial effects, chronic stress inhibits the immune response in mammals and teleost fish. In response to stress, a signaling cascade is triggered by the activation of neural circuits in the central nervous system because the hypothalamus is the central modulator of stress. This leads to the production of catecholamines, corticosteroid-releasing hormone, adrenocorticotropic hormone and glucocorticoids, which are the essential neuroendocrine mediators for this activation. Because stress situations are energetically demanding, the neuroendocrine signals are involved in metabolic support and will suppress the "less important" immune function. Understanding the cellular mechanisms of the neuroendocrine regulation of immunity in fish will allow the development of new pharmaceutical strategies and therapeutics for the prevention and treatment of diseases triggered by stress at all stages of fish cultures for commercial production. Copyright © 2014 Elsevier Ltd. All rights reserved.

High content image analysis for human H4 neuroglioma cells exposed to CuO nanoparticles.

PubMed

Li, Fuhai; Zhou, Xiaobo; Zhu, Jinmin; Ma, Jinwen; Huang, Xudong; Wong, Stephen T C

2007-10-09

High content screening (HCS)-based image analysis is becoming an important and widely used research tool. Capitalizing this technology, ample cellular information can be extracted from the high content cellular images. In this study, an automated, reliable and quantitative cellular image analysis system developed in house has been employed to quantify the toxic responses of human H4 neuroglioma cells exposed to metal oxide nanoparticles. This system has been proved to be an essential tool in our study. The cellular images of H4 neuroglioma cells exposed to different concentrations of CuO nanoparticles were sampled using IN Cell Analyzer 1000. A fully automated cellular image analysis system has been developed to perform the image analysis for cell viability. A multiple adaptive thresholding method was used to classify the pixels of the nuclei image into three classes: bright nuclei, dark nuclei, and background. During the development of our image analysis methodology, we have achieved the followings: (1) The Gaussian filtering with proper scale has been applied to the cellular images for generation of a local intensity maximum inside each nucleus; (2) a novel local intensity maxima detection method based on the gradient vector field has been established; and (3) a statistical model based splitting method was proposed to overcome the under segmentation problem. Computational results indicate that 95.9% nuclei can be detected and segmented correctly by the proposed image analysis system. The proposed automated image analysis system can effectively segment the images of human H4 neuroglioma cells exposed to CuO nanoparticles. The computational results confirmed our biological finding that human H4 neuroglioma cells had a dose-dependent toxic response to the insult of CuO nanoparticles.

Simulating Quantitative Cellular Responses Using Asynchronous Threshold Boolean Network Ensembles

EPA Science Inventory

With increasing knowledge about the potential mechanisms underlying cellular functions, it is becoming feasible to predict the response of biological systems to genetic and environmental perturbations. Due to the lack of homogeneity in living tissues it is difficult to estimate t...

The effect of growth phase and medium on the use of the firefly adenosine triphosphate (ATP) assay for the quantitation of bacteria

NASA Technical Reports Server (NTRS)

Bush, V. N.; Picciolo, G. L.; Chappelle, E. W.

1975-01-01

Luciferase assay for adenosine triphosphate (ATP) was used as a rapid method to determine the number of bacteria in a urine sample after nonbacterial components were removed. Accurate cellular ATP values, determined when bacteria were grown in an environment similar to that in which they were found, were necessary for the calculation of bacterial titer in urine. Cellular ATP values vary depending on the extraction method, the cell growth phase, and cell growth conditions. ATP per cell values of stationary E. coli grown in urine were two times greater than ATP per cell values of cells grown in trypticase soy broth. Glucose and urea were examined as possible components responsible for the cellular ATP variation.

Streamlining genomes: toward the generation of simplified and stabilized microbial systems.

PubMed

Leprince, Audrey; van Passel, Mark W J; dos Santos, Vitor A P Martins

2012-10-01

At the junction between systems and synthetic biology, genome streamlining provides a solid foundation both for increased understanding of cellular circuitry, and for the tailoring of microbial chassis towards innovative biotechnological applications. Iterative genomic deletions (targeted and random) helps to generate simplified, stabilized and predictable genomes, whereas multiplexing genome engineering reveals a broad functional genetic diversity. The decrease in oligo and gene synthesis costs promises effective combinatorial tools for the generation of chassis based on streamlined and tractable genomes. Here we review recent progresses in streamlining genomes through recombineering techniques aiming to generate insights into cellular mechanisms and responses towards the design and assembly of streamlined genome chassis together with new cellular modules in diverse biotechnological applications. Copyright © 2012 Elsevier Ltd. All rights reserved.

Discovery of plant extracts that greatly delay yeast chronological aging and have different effects on longevity-defining cellular processes

PubMed Central

Samson, Eugenie; Arlia-Ciommo, Anthony; Dakik, Pamela; Cortes, Berly; Feldman, Rachel; Mohtashami, Sadaf; McAuley, Mélissa; Chancharoen, Marisa; Rukundo, Belise; Simard, Éric; Titorenko, Vladimir I.

2016-01-01

We discovered six plant extracts that increase yeast chronological lifespan to a significantly greater extent than any of the presently known longevity-extending chemical compounds. One of these extracts is the most potent longevity-extending pharmacological intervention yet described. We show that each of the six plant extracts is a geroprotector which delays the onset and decreases the rate of yeast chronological aging by eliciting a hormetic stress response. We also show that each of these extracts has different effects on cellular processes that define longevity in organisms across phyla. These effects include the following: 1) increased mitochondrial respiration and membrane potential; 2) augmented or reduced concentrations of reactive oxygen species; 3) decreased oxidative damage to cellular proteins, membrane lipids, and mitochondrial and nuclear genomes; 4) enhanced cell resistance to oxidative and thermal stresses; and 5) accelerated degradation of neutral lipids deposited in lipid droplets. Our findings provide new insights into mechanisms through which chemicals extracted from certain plants can slow biological aging. PMID:26918729

AGCVIII Kinases: at the crossroads of cellular signaling

USDA-ARS?s Scientific Manuscript database

AGCVIII kinases regulate diverse developmental and cellular processes in plants. As putative mediators of secondary messengers, AGCVIII kinases potentially integrate developmental and environmental cues into specific cellular responses through substrate phosphorylation. Here we discuss the functiona...

Quillaja brasiliensis saponins induce robust humoral and cellular responses in a bovine viral diarrhea virus vaccine in mice.

PubMed

Cibulski, Samuel Paulo; Silveira, Fernando; Mourglia-Ettlin, Gustavo; Teixeira, Thais Fumaco; dos Santos, Helton Fernandes; Yendo, Anna Carolina; de Costa, Fernanda; Fett-Neto, Arthur Germano; Gosmann, Grace; Roehe, Paulo Michel

2016-04-01

A saponin fraction extracted from Quillaja brasiliensis leaves (QB-90) and a semi-purified aqueous extract (AE) were evaluated as adjuvants in a bovine viral diarrhea virus (BVDV) vaccine in mice. Animals were immunized on days 0 and 14 with antigen plus either QB-90 or AE or an oil-adjuvanted vaccine. Two-weeks after boosting, antibodies were measured by ELISA; cellular immunity was evaluated by DTH, lymphoproliferation, cytokine release and single cell IFN-γ production. Serum anti-BVDV IgG, IgG1 and IgG2b were significantly increased in QB-90- and AE-adjuvanted vaccines. A robust DTH response, increased splenocyte proliferation, Th1-type cytokines and enhanced production of IFN-γ by CD4(+) and CD8(+) T lymphocytes were detected in mice that received QB-90-adjuvanted vaccine. The AE-adjuvanted preparation stimulated humoral responses but not cellular immune responses. These findings reveal that QB-90 is capable of stimulating both cellular and humoral immune responses when used as adjuvant. Copyright © 2016 Elsevier Ltd. All rights reserved.

Cellular burdens and biological effects on tissue level caused by inhaled radon progenies.

PubMed

Madas, B G; Balásházy, I; Farkas, Á; Szoke, I

2011-02-01

In the case of radon exposure, the spatial distribution of deposited radioactive particles is highly inhomogeneous in the central airways. The object of this research is to investigate the consequences of this heterogeneity regarding cellular burdens in the bronchial epithelium and to study the possible biological effects at tissue level. Applying computational fluid and particle dynamics techniques, the deposition distribution of inhaled radon daughters has been determined in a bronchial airway model for 23 min of work in the New Mexico uranium mine corresponding to 0.0129 WLM exposure. A numerical epithelium model based on experimental data has been utilised in order to quantify cellular hits and doses. Finally, a carcinogenesis model considering cell death-induced cell-cycle shortening has been applied to assess the biological responses. Present computations reveal that cellular dose may reach 1.5 Gy, which is several orders of magnitude higher than tissue dose. The results are in agreement with the histological finding that the uneven deposition distribution of radon progenies may lead to inhomogeneous spatial distribution of tumours in the bronchial airways. In addition, at the macroscopic level, the relationship between cancer risk and radiation burden seems to be non-linear.

Protein Corona Analysis of Silver Nanoparticles Links to Their Cellular Effects.

PubMed

Juling, Sabine; Niedzwiecka, Alicia; Böhmert, Linda; Lichtenstein, Dajana; Selve, Sören; Braeuning, Albert; Thünemann, Andreas F; Krause, Eberhard; Lampen, Alfonso

2017-11-03

The breadth of applications of nanoparticles and the access to food-associated consumer products containing nanosized materials lead to oral human exposure to such particles. In biological fluids nanoparticles dynamically interact with biomolecules and form a protein corona. Knowledge about the protein corona is of great interest for understanding the molecular effects of particles as well as their fate inside the human body. We used a mass spectrometry-based toxicoproteomics approach to elucidate mechanisms of toxicity of silver nanoparticles and to comprehensively characterize the protein corona formed around silver nanoparticles in Caco-2 human intestinal epithelial cells. Results were compared with respect to the cellular function of proteins either affected by exposure to nanoparticles or present in the protein corona. A transcriptomic data set was included in the analyses in order to obtain a combined multiomics view of nanoparticle-affected cellular processes. A relationship between corona proteins and the proteomic or transcriptomic responses was revealed, showing that differentially regulated proteins or transcripts were engaged in the same cellular signaling pathways. Protein corona analyses of nanoparticles in cells might therefore help in obtaining information about the molecular consequences of nanoparticle treatment.

A Quantitative Study of Oxygen as a Metabolic Regulator

NASA Technical Reports Server (NTRS)

Radhakrishnan, Krishnan; LaManna, Joseph C.; Cabera, Marco E.

2000-01-01

An acute reduction in oxygen delivery to a tissue is associated with metabolic changes aimed at maintaining ATP homeostasis. However, given the complexity of the human bio-energetic system, it is difficult to determine quantitatively how cellular metabolic processes interact to maintain ATP homeostasis during stress (e.g., hypoxia, ischemia, and exercise). In particular, we are interested in determining mechanisms relating cellular oxygen concentration to observed metabolic responses at the cellular, tissue, organ, and whole body levels and in quantifying how changes in tissue oxygen availability affect the pathways of ATP synthesis and the metabolites that control these pathways. In this study; we extend a previously developed mathematical model of human bioenergetics, to provide a physicochemical framework that permits quantitative understanding of oxygen as a metabolic regulator. Specifically, the enhancement - sensitivity analysis - permits studying the effects of variations in tissue oxygenation and parameters controlling cellular respiration on glycolysis, lactate production, and pyruvate oxidation. The analysis can distinguish between parameters that must be determined accurately and those that require less precision, based on their effects on model predictions. This capability may prove to be important in optimizing experimental design, thus reducing use of animals.

Metal ions induced heat shock protein response by elevating superoxide anion level in HeLa cells transformed by HSE-SEAP reporter gene.

PubMed

Yu, Zhanjiang; Yang, Xiaoda; Wang, Kui

2006-06-01

The aim of this work is to define the relationship between heat shock protein (HSP) and reactive oxygen species (ROS) in the cells exposed to different concentrations of metal ions, and to evaluate a new method for tracing the dynamic levels of cellular reactive oxygen species using a HSE-SEAP reporter gene. The expression of heat shock protein was measured using a secreted alkaline phosphatase (SEAP) reporter gene transformed into HeLa cell strain, the levels of superoxide anion (O(2)(-)) and hydrogen peroxide (H(2)O(2)) were determined by NBT reduction assay and DCFH staining flow cytometry (FCM), respectively. The experimental results demonstrated that the expression of heat shock protein induced by metal ions was linearly related to the cellular superoxide anion level before cytotoxic effects were observed, but not related to the cellular hydrogen peroxide level. The experimental results suggested that metal ions might induce heat shock protein by elevating cellular superoxide anion level, and thus the expression of heat shock protein indicated by the HSE-SEAP reporter gene can be an effective model for monitoring the dynamic level of superoxide anion and early metal-induced oxidative stress/cytotoxicity.

Controlled Human Malaria Infection (CHMI) differentially affects cell-mediated and antibody responses to CSP and AMA1 induced by adenovirus vaccines with and without DNA-priming.

PubMed

Sedegah, Martha; Hollingdale, Michael R; Farooq, Fouzia; Ganeshan, Harini; Belmonte, Maria; Huang, Jun; Abot, Esteban; Limbach, Keith; Chuang, Ilin; Tamminga, Cindy; Epstein, Judith E; Villasante, Eileen

2015-01-01

We have previously shown that a DNA-prime followed by an adenovirus-5 boost vaccine containing CSP and AMA1 (DNA/Ad) successfully protected 4 of 15 subjects to controlled human malaria infection (CHMI). However, the adenovirus-5 vaccine alone (AdCA) failed to induce protection despite eliciting cellular responses that were often higher than those induced by DNA/Ad. Here we determined the effect of CHMI on pre-CHMI cellular and antibody responses against CSP and AMA1 expressed as fold-changes in activities. Generally, in the DNA/Ad trial, CHMI caused pre-CHMI ELISpot IFN-γ and CD8+ T cell IFN-γ responses of the protected subjects to fall but among non-protected subjects, CHMI caused rises of pre-CHMI ELISpot IFN-γ but falls of CD8+ T cell IFN-γ responses. In contrast in the AdCA trial, CHMI caused both pre-CHMI ELISpot IFN-γ and CD8+ T cell IFN-γ responses of the AdCA subjects to fall. We suggest that the falls in activities are due to migration of peripheral CD8+ T cells to the liver in response to developing liver stage parasites, and this fall, in the DNA/Ad trial, is masked in ELISpot responses of the non-protected subjects by rises in other immune cell types. In addition, CHMI caused falls in antibody activities of protected subjects, but rises in non-protected subjects in both trials to CSP, and dramatically in the AdCA trial to AMA1, reaching 380 μg/ml that is probably due to boosting by transient blood stage infection before chloroquine treatment. Taken together, these results further define differences in cellular responses between DNA/Ad and AdCA trials, and suggest that natural transmission may boost responses induced by these malaria vaccines especially when protection is not achieved.

Impact of labile metal nanoparticles on cellular homeostasis. Current developments in imaging, synthesis and applications.

PubMed

Chevallet, Mireille; Veronesi, Giulia; Fuchs, Alexandra; Mintz, Elisabeth; Michaud-Soret, Isabelle; Deniaud, Aurélien

2017-06-01

The use of nanomaterials is constantly increasing in electronics, cosmetics, food additives, and is emerging in advanced biomedical applications such as theranostics, bio-imaging and therapeutics. However their safety raises concerns and requires appropriate methods to analyze their fate in vivo. In this review, we describe the current knowledge about the toxicity of labile metal (ZnO, CuO and Ag) nanoparticles (NPs) both at the organism and cellular levels, and describe the pathways that are triggered to maintain cellular homeostasis. We also describe advanced elemental imaging approaches to analyze intracellular NP fate. Finally, we open the discussion by presenting recent developments in terms of synthesis and applications of Ag and CuO NPs. Labile metal nanoparticles (MeNPs) release metal ions that trigger a cellular response involving biomolecules binding to the ions followed by regulation of the redox balance. In addition, specific mechanisms are set up by the cell in response to physiological ions such as Cu(I) and Zn(II). Among all types of NPs, labile MeNPs induce the strongest inflammatory responses which are most probably due to the combined effects of the NPs and of its released ions. Interestingly, recent developments in imaging technologies enable the intracellular visualization of both the NPs and their ions and promise new insights into nanoparticle fate and toxicity. The exponential use of nanotechnologies associated with the difficulties of assessing their impact on health and the environment has prompted scientists to develop novel methodologies to characterize these nanoobjects in a biological context. Copyright © 2016 Elsevier B.V. All rights reserved.

Free radicals, reactive oxygen species, oxidative stress and its classification.

PubMed

Lushchak, Volodymyr I

2014-12-05

Reactive oxygen species (ROS) initially considered as only damaging agents in living organisms further were found to play positive roles also. This paper describes ROS homeostasis, principles of their investigation and technical approaches to investigate ROS-related processes. Especial attention is paid to complications related to experimental documentation of these processes, their diversity, spatiotemporal distribution, relationships with physiological state of the organisms. Imbalance between ROS generation and elimination in favor of the first with certain consequences for cell physiology has been called "oxidative stress". Although almost 30years passed since the first definition of oxidative stress was introduced by Helmut Sies, to date we have no accepted classification of oxidative stress. In order to fill up this gape here classification of oxidative stress based on its intensity is proposed. Due to that oxidative stress may be classified as basal oxidative stress (BOS), low intensity oxidative stress (LOS), intermediate intensity oxidative stress (IOS), and high intensity oxidative stress (HOS). Another classification of potential interest may differentiate three categories such as mild oxidative stress (MOS), temperate oxidative stress (TOS), and finally severe (strong) oxidative stress (SOS). Perspective directions of investigations in the field include development of sophisticated classification of oxidative stresses, accurate identification of cellular ROS targets and their arranged responses to ROS influence, real in situ functions and operation of so-called "antioxidants", intracellular spatiotemporal distribution and effects of ROS, deciphering of molecular mechanisms responsible for cellular response to ROS attacks, and ROS involvement in realization of normal cellular functions in cellular homeostasis. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

A Multiscale Computational Model of the Response of Swine Epidermis After Acute Irradiation

NASA Technical Reports Server (NTRS)

Hu, Shaowen; Cucinotta, Francis A.

2012-01-01

Radiation exposure from Solar Particle Events can lead to very high skin dose for astronauts on exploration missions outside the protection of the Earth s magnetic field [1]. Assessing the detrimental effects to human skin under such adverse conditions could be predicted by conducting territorial experiments on animal models. In this study we apply a computational approach to simulate the experimental data of the radiation response of swine epidermis, which is closely similar to human epidermis [2]. Incorporating experimentally measured histological and cell kinetic parameters into a multiscale tissue modeling framework, we obtain results of population kinetics and proliferation index comparable to unirradiated and acutely irradiated swine experiments [3]. It is noted the basal cell doubling time is 10 to 16 days in the intact population, but drops to 13.6 hr in the regenerating populations surviving irradiation. This complex 30-fold variation is proposed to be attributed to the shortening of the G1 phase duration. We investigate this radiation induced effect by considering at the sub-cellular level the expression and signaling of TGF-beta, as it is recognized as a key regulatory factor of tissue formation and wound healing [4]. This integrated model will allow us to test the validity of various basic biological rules at the cellular level and sub-cellular mechanisms by qualitatively comparing simulation results with published research, and should lead to a fuller understanding of the pathophysiological effects of ionizing radiation on the skin.

Mosaic HIV-1 vaccines expand the breadth and depth of cellular immune responses in rhesus monkeys.

PubMed

Barouch, Dan H; O'Brien, Kara L; Simmons, Nathaniel L; King, Sharon L; Abbink, Peter; Maxfield, Lori F; Sun, Ying-Hua; La Porte, Annalena; Riggs, Ambryice M; Lynch, Diana M; Clark, Sarah L; Backus, Katherine; Perry, James R; Seaman, Michael S; Carville, Angela; Mansfield, Keith G; Szinger, James J; Fischer, Will; Muldoon, Mark; Korber, Bette

2010-03-01

The worldwide diversity of HIV-1 presents an unprecedented challenge for vaccine development. Antigens derived from natural HIV-1 sequences have elicited only a limited breadth of cellular immune responses in nonhuman primate studies and clinical trials to date. Polyvalent 'mosaic' antigens, in contrast, are designed to optimize cellular immunologic coverage of global HIV-1 sequence diversity. Here we show that mosaic HIV-1 Gag, Pol and Env antigens expressed by recombinant, replication-incompetent adenovirus serotype 26 vectors markedly augmented both the breadth and depth without compromising the magnitude of antigen-specific T lymphocyte responses as compared with consensus or natural sequence HIV-1 antigens in rhesus monkeys. Polyvalent mosaic antigens therefore represent a promising strategy to expand cellular immunologic vaccine coverage for genetically diverse pathogens such as HIV-1.

Methodological considerations for global analysis of cellular FLIM/FRET measurements

NASA Astrophysics Data System (ADS)

Adbul Rahim, Nur Aida; Pelet, Serge; Kamm, Roger D.; So, Peter T. C.

2012-02-01

Global algorithms can improve the analysis of fluorescence energy transfer (FRET) measurement based on fluorescence lifetime microscopy. However, global analysis of FRET data is also susceptible to experimental artifacts. This work examines several common artifacts and suggests remedial experimental protocols. Specifically, we examined the accuracy of different methods for instrument response extraction and propose an adaptive method based on the mean lifetime of fluorescent proteins. We further examined the effects of image segmentation and a priori constraints on the accuracy of lifetime extraction. Methods to test the applicability of global analysis on cellular data are proposed and demonstrated. The accuracy of global fitting degrades with lower photon count. By systematically tracking the effect of the minimum photon count on lifetime and FRET prefactors when carrying out global analysis, we demonstrate a correction procedure to recover the correct FRET parameters, allowing us to obtain protein interaction information even in dim cellular regions with photon counts as low as 100 per decay curve.

Integration of Proteomic, Transcriptional, and Interactome Data Reveals Hidden Signaling Components

PubMed Central

Huang, Shao-shan Carol; Fraenkel, Ernest

2009-01-01

Cellular signaling and regulatory networks underlie fundamental biological processes such as growth, differentiation, and response to the environment. Although there are now various high-throughput methods for studying these processes, knowledge of them remains fragmentary. Typically, the vast majority of hits identified by transcriptional, proteomic, and genetic assays lie outside of the expected pathways. These unexpected components of the cellular response are often the most interesting, because they can provide new insights into biological processes and potentially reveal new therapeutic approaches. However, they are also the most difficult to interpret. We present a technique, based on the Steiner tree problem, that uses previously reported protein-protein and protein-DNA interactions to determine how these hits are organized into functionally coherent pathways, revealing many components of the cellular response that are not readily apparent in the original data. Applied simultaneously to phosphoproteomic and transcriptional data for the yeast pheromone response, it identifies changes in diverse cellular processes that extend far beyond the expected pathways. PMID:19638617

Cellular stress responses, mitostress and carnitine insufficiencies as critical determinants in aging and neurodegenerative disorders: role of hormesis and vitagenes.

PubMed

Calabrese, Vittorio; Cornelius, Carolin; Stella, Anna Maria Giuffrida; Calabrese, Edward J

2010-12-01

The widely accepted oxidative stress theory of aging postulates that aging results from accumulation of oxidative damage. A prediction of this theory is that, among species, differential rates of aging may be apparent on the basis of intrinsic differences in oxidative damage accrual. Although widely accepted, there is a growing number of exceptions to this theory, most contingently related to genetic model organism investigations. Proteins are one of the prime targets for oxidative damage and cysteine residues are particularly sensitive to reversible and irreversible oxidation. The adaptation and survival of cells and organisms requires the ability to sense proteotoxic insults and to coordinate protective cellular stress response pathways and chaperone networks related to protein quality control and stability. The toxic effects that stem from the misassembly or aggregation of proteins or peptides, in any cell type, are collectively termed proteotoxicity. Despite the abundance and apparent capacity of chaperones and other components of homeostasis to restore folding equilibrium, the cell appears poorly adapted for chronic proteotoxic stress which increases in cancer, metabolic and neurodegenerative diseases. Pharmacological modulation of cellular stress response pathways has emerging implications for the treatment of human diseases, including neurodegenerative disorders, cardiovascular disease, and cancer. A critical key to successful medical intervention is getting the dose right. Achieving this goal can be extremely challenging due to human inter-individual variation as affected by age, gender, diet, exercise, genetic factors and health status. The nature of the dose response in and adjacent to the therapeutic zones, over the past decade has received considerable advances. The hormetic dose-response, challenging long-standing beliefs about the nature of the dose-response in a lowdose zone, has the potential to affect significantly the design of pre-clinical studies and clinical trials as well as strategies for optimal patient dosing in the treatment of numerous diseases. Given the broad cytoprotective properties of the heat shock response there is now strong interest in discovering and developing pharmacological agents capable of inducing stress responses, including carnitines. This paper describes in mechanistic detail how hormetic dose responses are mediated for endogenous cellular defense pathways, including the possible signaling mechanisms by which the carnitine system, by interplaying metabolism, mitochondrial energetics and activation of critical vitagenes, modulates signal transduction cascades that confer cytoprotection against chronic degenerative damage associated to aging and neurodegenerative disorders.

Interactions between genetic variation and cellular environment in skeletal muscle gene expression.

PubMed

Taylor, D Leland; Knowles, David A; Scott, Laura J; Ramirez, Andrea H; Casale, Francesco Paolo; Wolford, Brooke N; Guan, Li; Varshney, Arushi; Albanus, Ricardo D'Oliveira; Parker, Stephen C J; Narisu, Narisu; Chines, Peter S; Erdos, Michael R; Welch, Ryan P; Kinnunen, Leena; Saramies, Jouko; Sundvall, Jouko; Lakka, Timo A; Laakso, Markku; Tuomilehto, Jaakko; Koistinen, Heikki A; Stegle, Oliver; Boehnke, Michael; Birney, Ewan; Collins, Francis S

2018-01-01

From whole organisms to individual cells, responses to environmental conditions are influenced by genetic makeup, where the effect of genetic variation on a trait depends on the environmental context. RNA-sequencing quantifies gene expression as a molecular trait, and is capable of capturing both genetic and environmental effects. In this study, we explore opportunities of using allele-specific expression (ASE) to discover cis-acting genotype-environment interactions (GxE)-genetic effects on gene expression that depend on an environmental condition. Treating 17 common, clinical traits as approximations of the cellular environment of 267 skeletal muscle biopsies, we identify 10 candidate environmental response expression quantitative trait loci (reQTLs) across 6 traits (12 unique gene-environment trait pairs; 10% FDR per trait) including sex, systolic blood pressure, and low-density lipoprotein cholesterol. Although using ASE is in principle a promising approach to detect GxE effects, replication of such signals can be challenging as validation requires harmonization of environmental traits across cohorts and a sufficient sampling of heterozygotes for a transcribed SNP. Comprehensive discovery and replication will require large human transcriptome datasets, or the integration of multiple transcribed SNPs, coupled with standardized clinical phenotyping.

Developing a gene biomarker at the tipping point of adaptive and adverse responses in human bronchial epithelial cells

EPA Science Inventory

Determining mechanism-based biomarkers that distinguish adaptive and adverse cellular processes is critical to understanding the health effects of environmental exposures. Shifting from in vivo, low-throughput toxicity studies to high-throughput screening (HTS) paradigms and risk...

Spaceflight Effects and Molecular Responses in the Mouse Eye: Observations After Shuttle Mission STS-133

NASA Technical Reports Server (NTRS)

Prospero-Ponce, Claudia; Zanello, Susana B.; CoreyTheriot, Patricia; Chevez-Barrios, P.

2012-01-01

Microgravity-induced cephalad fluid shift and radiation exposure are some of the stressors seen in space exploration. Ocular changes leading to visual impairment in astronauts are of occupational health relevance. Therefore, we analyzed the effects of space flight in the eyes of mice. Six mice were assigned to Flight (FLT), Animal enclosure Module (AEM), or vivarium (VIV) group, respectively. Mice were sacrificed at 1, 5 or 7 days after landing from space. One eye was used for histological and immunohistoche-mistry analysis and the other eye for gene expression profiling. 8-OHdG and caspase-3 immunoreactivity were increased in the retina in FLT samples at return(R+1) compared to AEM/VIV groups, and decreased at day 7 (R+7). beta-amyloid was seen in the nerve fibers at the post-laminar region of the optic nerve in the flight samples (R+7). In addition, oxidative and cellular stress response genes were upregulated in the retina of FLT samples upon landing, and decreased by R+7. According to the results, a reversible molecular damage may occur in the retina of mice exposed to spaceflight followed by protective cellular response.

Osmotic stress adaptation of Paracoccidioides lutzii, Pb01, monitored by proteomics.

PubMed

Rodrigues, Leandro Nascimento da Silva; Brito, Wesley de Almeida; Parente, Ana Flávia Alves; Weber, Simone Schneider; Bailão, Alexandre Melo; Casaletti, Luciana; Borges, Clayton Luiz; Soares, Célia Maria de Almeida

2016-10-01

The ability to respond to stressful conditions is essential for most living organisms. In pathogenic organisms, this response is required for effective transition from a saprophytic lifestyle to the establishment of pathogenic interactions within a susceptible host. Hyperosmotic stress has been used as a model to study signal transduction and seems to cause many cellular adaptations, including the alteration of protein expression and cellular volume as well as size regulation. In this work, we evaluated the proteomic profile of Paracoccidioides lutzii Pb01 yeast cells during osmotic stress induced by potassium chloride. We performed a high accuracy proteomic technique (NanoUPLC-MS(E)) to identify differentially expressed proteins during osmotic shock. The data describe an osmoadaptative response of this fungus when subjected to this treatment. Proteins involved in the synthesis of cell wall components were modulated, which suggested cell wall remodeling. In addition, alterations in the energy metabolism were observed. Furthermore, proteins involved in amino acid metabolism and hydrogen peroxide detoxification were modulated during osmotic stress. Our study suggests that P. lutzii Pb01. presents a vast osmoadaptative response that is composed of different proteins that act together to minimize the effects caused by osmotic stress. Copyright © 2016 Elsevier Inc. All rights reserved.

Ca²⁺-dependent repair of pneumolysin pores: A new paradigm for host cellular defense against bacterial pore-forming toxins.

PubMed

Wolfmeier, Heidi; Schoenauer, Roman; Atanassoff, Alexander P; Neill, Daniel R; Kadioglu, Aras; Draeger, Annette; Babiychuk, Eduard B

2015-09-01

Pneumolysin (PLY), a key virulence factor of Streptococcus pneumoniae, permeabilizes eukaryotic cells by forming large trans-membrane pores. PLY imposes a puzzling multitude of diverse, often mutually excluding actions on eukaryotic cells. Whereas cytotoxicity of PLY can be directly attributed to the pore-mediated effects, mechanisms that are responsible for the PLY-induced activation of host cells are poorly understood. We show that PLY pores can be repaired and thereby PLY-induced cell death can be prevented. Pore-induced Ca²⁺ entry from the extracellular milieu is of paramount importance for the initiation of plasmalemmal repair. Nevertheless, active Ca²⁺ sequestration that prevents excessive Ca²⁺ elevation during the execution phase of plasmalemmal repair is of no less importance. The efficacy of plasmalemmal repair does not only define the fate of targeted cells but also intensity, duration and repetitiveness of PLY-induced Ca²⁺ signals in cells that were able to survive after PLY attack. Intracellular Ca²⁺ dynamics evoked by the combined action of pore formation and their elimination mimic the pattern of receptor-mediated Ca²⁺ signaling, which is responsible for the activation of host immune responses. Therefore, we postulate that plasmalemmal repair of PLY pores might provoke cellular responses that are similar to those currently ascribed to the receptor-mediated PLY effects. Our data provide new insights into the understanding of the complexity of cellular non-immune defense responses to a major pneumococcal toxin that plays a critical role in the establishment and the progression of life-threatening diseases. Therapies boosting plasmalemmal repair of host cells and their metabolic fitness might prove beneficial for the treatment of pneumococcal infections. This article is part of a Special Issue entitled: 13th European Symposium on Calcium. Copyright © 2014 Elsevier B.V. All rights reserved.

Evaluation of PBS Treatment and PEI Coating Effects on Surface Morphology and Cellular Response of 3D-Printed Alginate Scaffolds.

PubMed

Mendoza García, María A; Izadifar, Mohammad; Chen, Xiongbiao

2017-11-01

Three-dimensional (3D) printing is an emerging technology for the fabrication of scaffolds to repair/replace damaged tissue/organs in tissue engineering. This paper presents our study on 3D printed alginate scaffolds treated with phosphate buffered saline (PBS) and polyethyleneimine (PEI) coating and their impacts on the surface morphology and cellular response of the printed scaffolds. In our study, sterile alginate was prepared by means of the freeze-drying method and then, used to prepare the hydrogel for 3D printing into calcium chloride, forming 3D scaffolds. Scaffolds were treated with PBS for a time period of two days and seven days, respectively, and PEI coating; then they were seeded with Schwann cells (RSC96) for the examination of cellular response (proliferation and differentiation). In addition, swelling and stiffness (Young's modulus) of the treated scaffolds was evaluated, while their surface morphology was assessed using scanning electron microscopy (SEM). SEM images revealed significant changes in scaffold surface morphology due to degradation caused by the PBS treatment over time. Our cell proliferation assessment over seven days showed that a two-day PBS treatment could be more effective than seven-day PBS treatment for improving cell attachment and elongation. While PEI coating of alginate scaffolds seemed to contribute to cell growth, Schwann cells stayed round on the surface of alginate over the period of cell culture. In conclusion, PBS-treatment may offer the potential to induce surface physical cues due to degradation of alginate, which could improve cell attachment post cell-seeding of 3D-printed alginate scaffolds.

Early effects of altered gravity environments on plant cell growth and cell proliferation: Characterization of morphofunctional nucleolar types in an Arabidopsis cell culture system

NASA Astrophysics Data System (ADS)

Manzano, Ana Isabel; Herranz, Raul; Manzano, Aránzazu; Van Loon, Jack; Medina, Francisco Javier

2016-02-01

Changes in the cell growth rate of an in vitro cellular system in Arabidopsis thaliana induced by short exposure to an altered gravity environment have been estimated by a novel approach. The method consisted of defining three structural nucleolar types which are easy and reliable indicators of the ribosome biogenesis activity and, consequently, of protein biosynthesis, a parameter strictly correlated to cell growth in this cellular system. The relative abundance of each nucleolar type was statistically assessed in different conditions of gravity. Samples exposed to simulated microgravity for 200 min showed a significant decrease in nucleolar activity compared to 1g controls, whereas samples exposed to hypergravity (2g) for the same period showed nucleolar activity slightly increased,. These effects could be considered as an early cellular response to the environmental alteration, given the short duration of the treatment. The functional significance of the structural data was validated by a combination of several different well-known parameters, using microscopical, flow cytometry, qPCR and proteomic approaches, which showed that the decreased cell growth rate was decoupled from an increased cell proliferation rate under simulated microgravity, and the opposite trend was observed under hypergravity. Actually, not all parameters tested showed the same quantitative changes, indicating that the response to the environmental alteration is time-dependent. These results are in agreement with previous observations in root meristematic cells and they show the ability of plant cells to produce a response to gravity changes, independently of their integration into plant organs.

Cellular Response of Pea Plants to Cadmium Toxicity: Cross Talk between Reactive Oxygen Species, Nitric Oxide, and Calcium1[W][OA

PubMed Central

Rodríguez-Serrano, María; Romero-Puertas, María C.; Pazmiño, Diana M.; Testillano, Pilar S.; Risueño, María C.; del Río, Luis A.; Sandalio, Luisa M.

2009-01-01

Cadmium (Cd) toxicity has been widely studied in different plant species; however, the mechanism involved in its toxicity as well as the cell response against the metal have not been well established. In this work, using pea (Pisum sativum) plants, we studied the effect of Cd on antioxidants, reactive oxygen species (ROS), and nitric oxide (NO) metabolism of leaves using different cellular, molecular, and biochemical approaches. The growth of pea plants with 50 μm CdCl2 affected differentially the expression of superoxide dismutase (SOD) isozymes at both transcriptional and posttranscriptional levels, giving rise to a SOD activity reduction. The copper/zinc-SOD down-regulation was apparently due to the calcium (Ca) deficiency induced by the heavy metal. In these circumstances, the overproduction of the ROS hydrogen peroxide and superoxide could be observed in vivo by confocal laser microscopy, mainly associated with vascular tissue, epidermis, and mesophyll cells, and the production of superoxide radicals was prevented by exogenous Ca. On the other hand, the NO synthase-dependent NO production was strongly depressed by Cd, and treatment with Ca prevented this effect. Under these conditions, the pathogen-related proteins PrP4A and chitinase and the heat shock protein 71.2, were up-regulated, probably to protect cells against damages induced by Cd. The regulation of these proteins could be mediated by jasmonic acid and ethylene, whose contents increased by Cd treatment. A model is proposed for the cellular response to long-term Cd exposure consisting of cross talk between Ca, ROS, and NO. PMID:19279198

Methods for the Analysis of Protein Phosphorylation-Mediated Cellular Signaling Networks

NASA Astrophysics Data System (ADS)

White, Forest M.; Wolf-Yadlin, Alejandro

2016-06-01

Protein phosphorylation-mediated cellular signaling networks regulate almost all aspects of cell biology, including the responses to cellular stimulation and environmental alterations. These networks are highly complex and comprise hundreds of proteins and potentially thousands of phosphorylation sites. Multiple analytical methods have been developed over the past several decades to identify proteins and protein phosphorylation sites regulating cellular signaling, and to quantify the dynamic response of these sites to different cellular stimulation. Here we provide an overview of these methods, including the fundamental principles governing each method, their relative strengths and weaknesses, and some examples of how each method has been applied to the analysis of complex signaling networks. When applied correctly, each of these techniques can provide insight into the topology, dynamics, and regulation of protein phosphorylation signaling networks.

Impact of Viral Infections on Hematopoiesis: From Beneficial to Detrimental Effects on Bone Marrow Output

PubMed Central

Pascutti, Maria Fernanda; Erkelens, Martje N.; Nolte, Martijn A.

2016-01-01

The ability of the bone marrow (BM) to generate copious amounts of blood cells required on a daily basis depends on a highly orchestrated process of proliferation and differentiation of hematopoietic stem and progenitor cells (HSPCs). This process can be rapidly adapted under stress conditions, such as infections, to meet the specific cellular needs of the immune response and the ensuing physiological changes. This requires a tight regulation in order to prevent either hematopoietic failure or transformation. Although adaptation to bacterial infections or systemic inflammation has been studied and reviewed in depth, specific alterations of hematopoiesis to viral infections have received less attention so far. Viruses constantly pose a significant health risk and demand an adequate, balanced response from our immune system, which also affects the BM. In fact, both the virus itself and the ensuing immune response can have a tremendous impact on the hematopoietic process. On one hand, this can be beneficial: it helps to boost the cellular response of the body to resolve the viral infection. But on the other hand, when the virus and the resulting antiviral response persist, the inflammatory feedback to the hematopoietic system will become chronic, which can be detrimental for a balanced BM output. Chronic viral infections frequently have clinical manifestations at the level of blood cell formation, and we summarize which viruses can lead to BM pathologies, like aplastic anemia, pancytopenia, hemophagocytic lymphohistiocytosis, lymphoproliferative disorders, and malignancies. Regarding the underlying mechanisms, we address specific effects of acute and chronic viral infections on blood cell production. As such, we distinguish four different levels in which this can occur: (1) direct viral infection of HSPCs, (2) viral recognition by HSPCs, (3) indirect effects on HSPCs by inflammatory mediators, and (4) the role of the BM microenvironment on hematopoiesis upon virus infection. In conclusion, this review provides a comprehensive overview on how viral infections can affect the formation of new blood cells, aiming to advance our understanding of the underlying cellular and molecular mechanisms to improve the treatment of BM failure in patients. PMID:27695457

Impact of Viral Infections on Hematopoiesis: From Beneficial to Detrimental Effects on Bone Marrow Output.

PubMed

Pascutti, Maria Fernanda; Erkelens, Martje N; Nolte, Martijn A

2016-01-01

The ability of the bone marrow (BM) to generate copious amounts of blood cells required on a daily basis depends on a highly orchestrated process of proliferation and differentiation of hematopoietic stem and progenitor cells (HSPCs). This process can be rapidly adapted under stress conditions, such as infections, to meet the specific cellular needs of the immune response and the ensuing physiological changes. This requires a tight regulation in order to prevent either hematopoietic failure or transformation. Although adaptation to bacterial infections or systemic inflammation has been studied and reviewed in depth, specific alterations of hematopoiesis to viral infections have received less attention so far. Viruses constantly pose a significant health risk and demand an adequate, balanced response from our immune system, which also affects the BM. In fact, both the virus itself and the ensuing immune response can have a tremendous impact on the hematopoietic process. On one hand, this can be beneficial: it helps to boost the cellular response of the body to resolve the viral infection. But on the other hand, when the virus and the resulting antiviral response persist, the inflammatory feedback to the hematopoietic system will become chronic, which can be detrimental for a balanced BM output. Chronic viral infections frequently have clinical manifestations at the level of blood cell formation, and we summarize which viruses can lead to BM pathologies, like aplastic anemia, pancytopenia, hemophagocytic lymphohistiocytosis, lymphoproliferative disorders, and malignancies. Regarding the underlying mechanisms, we address specific effects of acute and chronic viral infections on blood cell production. As such, we distinguish four different levels in which this can occur: (1) direct viral infection of HSPCs, (2) viral recognition by HSPCs, (3) indirect effects on HSPCs by inflammatory mediators, and (4) the role of the BM microenvironment on hematopoiesis upon virus infection. In conclusion, this review provides a comprehensive overview on how viral infections can affect the formation of new blood cells, aiming to advance our understanding of the underlying cellular and molecular mechanisms to improve the treatment of BM failure in patients.

Comparative Transcriptome Profiling of an SV40-Transformed Human Fibroblast (MRC5CVI) and Its Untransformed Counterpart (MRC-5) in Response to UVB Irradiation

PubMed Central

Chang, Cheng-Wei; Chen, Chaang-Ray; Huang, Chao-Ying; Shu, Wun-Yi; Chiang, Chi-Shiun; Hong, Ji-Hong; Hsu, Ian C.

2013-01-01

Simian virus 40 (SV40) transforms cells through the suppression of tumor-suppressive responses by large T and small t antigens; studies on the effects of these two oncoproteins have greatly improved our knowledge of tumorigenesis. Large T antigen promotes cellular transformation by binding and inactivating p53 and pRb tumor suppressor proteins. Previous studies have shown that not all of the tumor-suppressive responses were inactivated in SV40-transformed cells; however, the underlying cause is not fully studied. In this study, we investigated the UVB-responsive transcriptome of an SV40-transformed fibroblast (MRC5CVI) and that of its untransformed counterpart (MRC-5). We found that, in response to UVB irradiation, MRC-5 and MRC5CVI commonly up-regulated the expression of oxidative phosphorylation genes. MRC-5 up-regulated the expressions of chromosome condensation, DNA repair, cell cycle arrest, and apoptotic genes, but MRC5CVI did not. Further cell death assays indicated that MRC5CVI was more sensitive than MRC-5 to UVB-induced cell death with increased caspase-3 activation; combining with the transcriptomic results suggested that MRC5CVI may undergo UVB-induced cell death through mechanisms other than transcriptional regulation. Our study provides a further understanding of the effects of SV40 transformation on cellular stress responses, and emphasizes the value of SV40-transformed cells in the researches of sensitizing neoplastic cells to radiations. PMID:24019915

Fasting: Molecular Mechanisms and Clinical Applications

PubMed Central

Longo, Valter D.; Mattson, Mark P.

2014-01-01

Fasting has been practiced for millennia, but only recently studies have shed light on its role in adaptive cellular responses that reduce oxidative damage and inflammation, optimize energy metabolism and bolster cellular protection. In lower eukaryotes, chronic fasting extends longevity in part by reprogramming metabolic and stress resistance pathways. In rodents intermittent or periodic fasting protects against diabetes, cancers, heart disease and neurodegeneration, while in humans it helps reduce obesity, hypertension, asthma and rheumatoid arthritis. Thus, fasting has the potential to delay aging and help prevent and treat diseases while minimizing the side effects caused by chronic dietary interventions. PMID:24440038

Sepsis and Septic Shock Strategies.

PubMed

Armstrong, Bracken A; Betzold, Richard D; May, Addison K

2017-12-01

Three therapeutic principles most substantially improve organ dysfunction and survival in sepsis: early, appropriate antimicrobial therapy; restoration of adequate cellular perfusion; timely source control. The new definitions of sepsis and septic shock reflect the inadequate sensitivity, specify, and lack of prognostication of systemic inflammatory response syndrome criteria. Sequential (sepsis-related) organ failure assessment more effectively prognosticates in sepsis and critical illness. Inadequate cellular perfusion accelerates injury and reestablishing perfusion limits injury. Multiple organ systems are affected by sepsis and septic shock and an evidence-based multipronged approach to systems-based therapy in critical illness results in improve outcomes. Copyright © 2017 Elsevier Inc. All rights reserved.

The nature of thrombosis induced by platinum and tungsten coils in saccular aneurysms.

PubMed

Byrne, J V; Hope, J K; Hubbard, N; Morris, J H

1997-01-01

To compare the efficacy and biocompatability of electrolytic and mechanically detachable embolization coils of two metal types. Experimental saccular aneurysms in pigs were used to assess embolization induced by platinum or tungsten coils. Longitudinal angiographic and histologic studies were performed on treated and untreated (control) aneurysms to compare thrombosis and cellular responses after embolization with electrolytically detachable platinum coils and with mechanically detached tungsten coils. Fewer tungsten than platinum coils were needed to induce thrombosis. The inflammatory response within the aneurysmal lumen was more florid in embolized aneurysms than in control aneurysms. No difference was found in the timing or extent of accumulation of eosinophils, lymphocytes, or polymorphs between the two coils used. Giant cell responses were more marked in treated aneurysms; tungsten coils more than platinum coils. The amount of collagen and fibrosis present increased over the study period and was similar in treated and control aneurysms. The coil type influenced the initial cellular response but had little effect on the rate or degree to which blood clot within the aneurysm was replaced by fibrous tissue.

Time- and polarity-dependent proteomic changes associated with homeostatic scaling at central synapses

PubMed Central

Schanzenbächer, Christoph T

2018-01-01

In homeostatic scaling at central synapses, the depth and breadth of cellular mechanisms that detect the offset from the set-point, detect the duration of the offset and implement a cellular response are not well understood. To understand the time-dependent scaling dynamics we treated cultured rat hippocampal cells with either TTX or bicucculline for 2 hr to induce the process of up- or down-scaling, respectively. During the activity manipulation we metabolically labeled newly synthesized proteins using BONCAT. We identified 168 newly synthesized proteins that exhibited significant changes in expression. To obtain a temporal trajectory of the response, we compared the proteins synthesized within 2 hr or 24 hr of the activity manipulation. Surprisingly, there was little overlap in the significantly regulated newly synthesized proteins identified in the early- and integrated late response datasets. There was, however, overlap in the functional categories that are modulated early and late. These data indicate that within protein function groups, different proteomic choices can be made to effect early and late homeostatic responses that detect the duration and polarity of the activity manipulation. PMID:29447110

Recombinant Flagellin-Porcine Circovirus Type 2 Cap Fusion Protein Promotes Protective Immune Responses in Mice

PubMed Central

Zhang, Chunyan; Zhu, Shanshan; Wei, Li; Yan, Xu; Wang, Jing; Quan, Rong; She, Ruiping; Hu, Fengjiao; Liu, Jue

2015-01-01

The Cap protein of porcine circovirus type 2 (PCV2) that serves as a major host-protective immunogen was used to develop recombinant vaccines for control of PCV2-associated diseases. Growing research data have demonstrated the high effectiveness of flagellin as an adjuvant for humoral and cellular immune responses. Here, a recombinant protein was designed by fusing a modified version of bacterial flagellin to PCV2 Cap protein and expressed in a baculovirus system. When administered without adjuvant to BALB/c mice, the flagellin-Cap fusion protein elicited stronger PCV2-specific IgG antibody response, higher neutralizing antibody levels, milder histopathological changes and lower viremia, as well as higher secretion of cytokines such as TNF-α and IFN-γ that conferred better protection against virus challenge than those in the recombinant Cap alone-inoculated mice. These results suggest that the recombinant Cap protein when fused to flagellin could elicit better humoral and cellular immune responses against PCV2 infection in a mouse model, thereby acting as an attractive candidate vaccine for control of the PCV2-associated diseases. PMID:26070075

Mechano-biological Coupling of Cellular Responses to Microgravity

NASA Astrophysics Data System (ADS)

Long, Mian; Wang, Yuren; Zheng, Huiqiong; Shang, Peng; Duan, Enkui; Lü, Dongyuan

2015-11-01

Cellular response to microgravity is a basic issue in space biological sciences as well as space physiology and medicine. It is crucial to elucidate the mechano-biological coupling mechanisms of various biological organisms, since, from the principle of adaptability, all species evolved on the earth must possess the structure and function that adapts their living environment. As a basic element of an organism, a cell usually undergoes mechanical and chemical remodeling to sense, transmit, transduce, and respond to the alteration of gravitational signals. In the past decades, new computational platforms and experimental methods/techniques/devices are developed to mimic the biological effects of microgravity environment from the viewpoint of biomechanical approaches. Mechanobiology of plant gravisensing in the responses of statolith movements along the gravity vector and the relevant signal transduction and molecular regulatory mechanisms are investigated at gene, transcription, and protein levels. Mechanotransduction of bone or immune cell responses and stem cell development and tissue histogenesis are elucidated under microgravity. In this review, several important issues are briefly discussed. Future issues on gravisensing and mechanotransducing mechanisms are also proposed for ground-based studies as well as space missions.

Differential cellular responses in healthy mice and in mice with established airway inflammation when exposed to hematite nanoparticles.

PubMed

Gustafsson, Åsa; Bergström, Ulrika; Ågren, Lina; Österlund, Lars; Sandström, Thomas; Bucht, Anders

2015-10-01

The aim of this study was to investigate the inflammatory and immunological responses in airways and lung-draining lymph nodes (LDLNs), following lung exposure to iron oxide (hematite) nanoparticles (NPs). The responses to the hematite NPs were evaluated in both healthy non-sensitized mice, and in sensitized mice with an established allergic airway disease. The mice were exposed intratracheally to either hematite NPs or to vehicle (PBS) and the cellular responses were evaluated on days 1, 2, and 7, post-exposure. Exposure to hematite NPs increased the numbers of neutrophils, eosinophils, and lymphocytes in the airways of non-sensitized mice on days 1 and 2 post-exposure; at these time points the number of lymphocytes was also elevated in the LDLNs. In contrast, exposing sensitized mice to hematite NPs induced a rapid and unspecific cellular reduction in the alveolar space on day 1 post-exposure; a similar decrease of lymphocytes was also observed in the LDLN. The results indicate that cells in the airways and in the LDLN of individuals with established airway inflammation undergo cell death when exposed to hematite NPs. A possible explanation for this toxic response is the extensive generation of reactive oxygen species (ROS) in the pro-oxidative environment of inflamed airways. This study demonstrates how sensitized and non-sensitized mice respond differently to hematite NP exposure, and it highlights the importance of including individuals with respiratory disorders when evaluating health effects of inhaled nanomaterials. Copyright © 2015 Elsevier Inc. All rights reserved.

Increased sensitivity of thyroid hormone-mediated signaling despite prolonged fasting.

PubMed

Martinez, Bridget; Scheibner, Michael; Soñanez-Organis, José G; Jaques, John T; Crocker, Daniel E; Ortiz, Rudy M

2017-10-01

Thyroid hormones (TH) can increase cellular metabolism. Food deprivation in mammals is typically associated with reduced thyroid gland responsiveness, in an effort to suppress cellular metabolism and abate starvation. However, in prolonged-fasted, elephant seal pups, cellular TH-mediated proteins are up-regulated and TH levels are maintained with fasting duration. The function and contribution of the thyroid gland to this apparent paradox is unknown and physiologically perplexing. Here we show that the thyroid gland remains responsive during prolonged food deprivation, and that its function and production of TH increase with fasting duration in elephant seals. We discovered that our modeled plasma TH data in response to exogenous thyroid stimulating hormone predicted cellular signaling, which was corroborated independently by the enzyme expression data. The data suggest that the regulation and function of the thyroid gland in the northern elephant seal is atypical for a fasted animal, and can be better described as, "adaptive fasting". Furthermore, the modeling data help substantiate the in vivo responses measured, providing unique insight on hormone clearance, production rates, and thyroid gland responsiveness. Because these unique endocrine responses occur simultaneously with a nearly strict reliance on the oxidation of lipid, these findings provide an intriguing model to better understand the TH-mediated reliance on lipid metabolism that is not otherwise present in morbidly obese humans. When coupled with cellular, tissue-specific responses, these data provide a more integrated assessment of thyroidal status that can be extrapolated for many fasting/food deprived mammals. Copyright © 2017 Elsevier Inc. All rights reserved.

Pilot study of whole-blood gamma interferon response to the Vibrio cholerae toxin B subunit and resistance to enterotoxigenic Escherichia coli-associated diarrhea.

PubMed

Flores, Jose; DuPont, Herbert L; Paredes-Paredes, Mercedes; Aguirre-Garcia, M Magdalena; Rojas, Araceli; Gonzalez, Alexei; Okhuysen, Pablo C

2010-05-01

Enterotoxigenic Escherichia coli (ETEC), which produces heat-labile toxin (LT), is a common cause of travelers' diarrhea (TD). The B subunit of ETEC LT is immunologically related to the B subunit of Vibrio cholerae toxin (CT). In this pilot study we evaluated the whole-blood gamma interferon response to CT B in 17 U.S. adults traveling to Mexico. Only one of nine subjects who demonstrated a cellular immune response as determined by whole-blood gamma interferon production to CT B on arrival to Mexico developed diarrhea, whereas five of eight without a cellular response developed diarrhea. Markers of the cellular immune response to ETEC LT could help in identifying individuals immune to ETEC LT, and these markers deserve additional study.

Pairing of heterochromatin in response to cellular stress.

PubMed

Abdel-Halim, H I; Mullenders, L H F; Boei, J J W A

2006-07-01

We previously reported that exposure of human cells to DNA-damaging agents (X-rays and mitomycin C (MMC)) induces pairing of the homologous paracentromeric heterochromatin of chromosome 9 (9q12-13). Here, we show that UV irradiation and also heat shock treatment of human cells lead to similar effects. Since the various agents induce very different types and frequencies of damage to cellular constituents, the data suggest a general stress response as the underlying mechanism. Moreover, local UV irradiation experiments revealed that pairing of heterochromatin is an event that can be triggered without induction of DNA damage in the heterochromatic sequences. The repair deficient xeroderma pigmentosum cells (group F) previously shown to fail pairing after MMC displayed elevated pairing after heat shock treatment but not after UV exposure. Taken together, the present results indicate that pairing of heterochromatin following exposure to DNA-damaging agents is initiated by a general stress response and that the sensing of stress or the maintenance of the paired status of the heterochromatin might be dependent on DNA repair.

Functional Performances of CuZnAl Shape Memory Alloy Open-Cell Foams

NASA Astrophysics Data System (ADS)

Biffi, C. A.; Casati, R.; Bassani, P.; Tuissi, A.

2018-01-01

Shape memory alloys (SMAs) with cellular structure offer a unique mixture of thermo-physical-mechanical properties. These characteristics can be tuned by changing the pore size and make the shape memory metallic foams very attractive for developing new devices for structural and functional applications. In this work, CuZnAl SMA foams were produced through the liquid infiltration of space holder method. In comparison, a conventional CuZn brass alloy was foamed trough the same method. Functional performances were studied on both bulk and foamed SMA specimens. Calorimetric response shows similar martensitic transformation (MT) below 0 °C. Compressive response of CuZnAl revealed that mechanical behavior is strongly affected by sample morphology and that damping capacity of metallic foam is increased above the MT temperatures. The shape memory effect was detected in the CuZnAl foams. The conventional brass shows a compressive response similar to that of the martensitic CuZnAl, in which plastic deformation accumulation occurs up to the cellular structure densification after few thermal cycles.

Monocyte Chemotactic Protein 1 in Plasma from Soluble Leishmania Antigen-Stimulated Whole Blood as a Potential Biomarker of the Cellular Immune Response to Leishmania infantum

PubMed Central

Ibarra-Meneses, Ana V.; Sanchez, Carmen; Alvar, Jorge; Moreno, Javier; Carrillo, Eugenia

2017-01-01

New biomarkers are needed to identify asymptomatic Leishmania infection as well as immunity following vaccination or treatment. With the aim of finding a robust biomarker to assess an effective cellular immune response, monocyte chemotactic protein 1 (MCP-1) was examined in plasma from soluble Leishmania antigen (SLA)-stimulated whole blood collected from subjects living in a Leishmania infantum-endemic area. MCP-1, expressed 110 times more strongly than IL-2, identified 87.5% of asymptomatic subjects and verified some asymptomatic subjects close to the cutoff. MCP-1 was also significantly elevated in all patients cured of visceral leishmaniasis (VL), unlike IL-2, indicating the specific memory response generated against Leishmania. These results show MCP-1 to be a robust candidate biomarker of immunity that could be used as a marker of cure and to both select and follow the population in vaccine phase I–III human clinical trials with developed rapid, easy-to-use field tools. PMID:29033933

Transcriptome profiling and physiological studies reveal a major role for aromatic amino acids in mercury stress tolerance in rice seedlings.

PubMed

Chen, Yun-An; Chi, Wen-Chang; Trinh, Ngoc Nam; Huang, Li-Yao; Chen, Ying-Chih; Cheng, Kai-Teng; Huang, Tsai-Lien; Lin, Chung-Yi; Huang, Hao-Jen

2014-01-01

Mercury (Hg) is a serious environmental pollution threat to the planet. The accumulation of Hg in plants disrupts many cellular-level functions and inhibits growth and development, but the mechanism is not fully understood. To gain more insight into the cellular response to Hg, we performed a large-scale analysis of the rice transcriptome during Hg stress. Genes induced with short-term exposure represented functional categories of cell-wall formation, chemical detoxification, secondary metabolism, signal transduction and abiotic stress response. Moreover, Hg stress upregulated several genes involved in aromatic amino acids (Phe and Trp) and increased the level of free Phe and Trp content. Exogenous application of Phe and Trp to rice roots enhanced tolerance to Hg and effectively reduced Hg-induced production of reactive oxygen species. Hg induced calcium accumulation and activated mitogen-activated protein kinase. Further characterization of the Hg-responsive genes we identified may be helpful for better understanding the mechanisms of Hg in plants.

Biomarkers for immunotherapy in genitourinary malignancies.

PubMed

Slovin, Susan F

2016-04-01

Immunotherapy for genitourinary malignancies such as prostate, renal, and bladder cancers has experienced a resurgence since the development of 3 novel strategies: the autologous cellular product therapy, Sipuleucel-T for prostate cancer, the checkpoint inhibitors, anti-cytotoxic T-lymphocyte-associated protein 4 (anti-CTLA-4), anti-programmed cell death ligand 1 (anti-PD1), and anti-programmed cell death ligand 1), respectively. These agents have led to strikingly durable responses in several of these solid tumors, but their efficacy has been inconsistent. Why all solid tumors are not equal in their response to these therapies is unclear. More importantly, changes in humoral or cellular responses which may reflect changes in a tumor's biology have been limited due to differences in immune monitoring and lack of consistency in established reliable immunologic endpoints. How to design immunologic end points that reflect a meaningful effect on the cancer remains a challenge for clinical trial development. The issues faced by clinical investigators and the current state of immune monitoring are discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

The Emerging Role of IGF-1 Deficiency in Cardiovascular Aging: Recent Advances

PubMed Central

Csiszar, Anna

2012-01-01

This review focuses on cardiovascular protective effects of insulin-like growth factor (IGF)-1, provides a landscape of molecular mechanisms involved in cardiovascular alterations in patients and animal models with congenital and adult-onset IGF-1 deficiency, and explores the link between age-related IGF-1 deficiency and the molecular, cellular, and functional changes that occur in the cardiovascular system during aging. Microvascular protection conferred by endocrine and paracrine IGF-1 signaling, its implications for the pathophysiology of cardiac failure and vascular cognitive impairment, and the role of impaired cellular stress resistance in cardiovascular aging considered here are based on emerging knowledge of the effects of IGF-1 on Nrf2-driven antioxidant response. PMID:22451468

Effects of Cerium Oxide Nanoparticles on the Growth of Keratinocytes, Fibroblasts and Vascular Endothelial Cells in Cutaneous Wound Healing

PubMed Central

Chigurupati, Srinivasulu; Mughal, Mohamed R.; Okun, Eitan; Das, Soumen; Kumar, Amit; McCaffery, Michael; Seal, Sudipta; Mattson, Mark P.

2012-01-01

Rapid and effective wound healing requires a coordinated cellular response involving fibroblasts, keratinocytes and vascular endothelial cells (VECs). Impaired wound healing can result in multiple adverse health outcomes and, although antibiotics can forestall infection, treatments that accelerate wound healing are lacking. We now report that topical application of water soluble cerium oxide nanoparticles (Nanoceria) accelerates the healing of full-thickness dermal wounds in mice by a mechanism that involves enhancement of the proliferation and migration of fibroblasts, keratinocytes and VECs. The Nanoceria penetrated into the wound tissue and reduced oxidative damage to cellular membranes and proteins, suggesting a therapeutic potential for topical treatment of wounds with antioxidant nanoparticles. PMID:23266256

Assessment of Different Strategies to Determine MAP-specific Cellular Immune Responses in Cattle

USDA-ARS?s Scientific Manuscript database

Assessment of cellular immunity in cattle against Mycobacterium avium ssp. paratuberculosis (MAP) by established methods remains unsatisfactory for diagnostic purposes. Recent studies conclude that analysis of T-cell subset responsiveness may improve diagnostic outcome. Aim of this study was to iden...

Jack bean (Canavalia ensiformis) urease induces eicosanoid-modulated hemocyte aggregation in the Chagas' disease vector Rhodnius prolixus.

PubMed

Defferrari, M S; da Silva, R; Orchard, I; Carlini, C R

2014-05-01

Ureases are multifunctional proteins that display biological activities independently of their enzymatic function, such as induction of exocytosis and insecticidal effects. Rhodnius prolixus, a major vector of Chagas' disease, is a model for studies on the entomotoxicity of jack bean urease (JBU). We have previously shown that JBU induces the production of eicosanoids in isolated tissues of R. prolixus. In insects, the immune response comprises cellular and humoral reactions, and is centrally modulated by eicosanoids. Cyclooxygenase products signal immunity in insects, mainly cellular reactions, such as hemocyte aggregation. In searching for a link between JBU's toxic effects and immune reactions in insects, we have studied the effects of this toxin on R. prolixus hemocytes. JBU triggers aggregation of hemocytes after injection into the hemocoel and when applied to isolated cells. On in vitro assays, the eicosanoid synthesis inhibitors dexamethasone (phospholipase A2 indirect inhibitor) and indomethacin (cyclooxygenase inhibitor) counteracted JBU's effect, indicating that eicosanoids, more specifically cyclooxygenase products, are likely to mediate the aggregation response. Contrarily, the inhibitors esculetin and baicalein were inactive, suggesting that lipoxygenase products are not involved in JBU's effect. Extracellular calcium was also necessary for JBU's effect, in agreement to other cell models responsive to ureases. A progressive darkening of the medium of JBU-treated hemocytes was observed, suggestive of a humoral response. JBU was immunolocalized in the cultured cells upon treatment along with cytoskeleton damage. The highest concentration of JBU tested on cultured cells also led to nuclei aggregation of adherent hemocytes. This is the first time urease has been shown to affect insect hemocytes, contributing to our understanding of the entomotoxic mechanisms of action of this protein. Copyright © 2014 Elsevier Ltd. All rights reserved.

Oral Combination Vaccine, Comprising Bifidobacterium Displaying Hepatitis C Virus Nonstructural Protein 3 and Interferon-α, Induces Strong Cellular Immunity Specific to Nonstructural Protein 3 in Mice.

PubMed

Kitagawa, Koichi; Omoto, Chika; Oda, Tsugumi; Araki, Ayame; Saito, Hiroki; Shigemura, Katsumi; Katayama, Takane; Hotta, Hak; Shirakawa, Toshiro

2017-04-01

We previously generated an oral hepatitis C virus (HCV) vaccine using Bifidobacterium displaying the HCV nonstructural protein 3 (NS3) polypeptide. NS3-specific cellular immunity is important for viral clearance and recovery from HCV infection. In this study, we enhanced the cellular immune responses induced by our oral HCV vaccine, Bifidobacterium longum 2165 (B. longum 2165), by combining interferon-α (IFN-α) as an adjuvant with the vaccine in a mouse experimental model. IFN-α is a widely used cytokine meeting the standard of care (SOC) for HCV infection and plays various immunoregulatory roles. We treated C57BL/6N mice with B. longum 2165 every other day and/or IFN-α twice a week for a month and then analyzed the immune responses using spleen cells. We determined the induction of NS3-specific cellular immunity by cytokine quantification, intracellular cytokine staining, and a cytotoxic T lymphocyte (CTL) assay targeting EL4 tumor cells expressing NS3/4A protein (EL4-NS3/4A). We also treated mice bearing EL4-NS3/4A tumor with the combination therapy in vivo. The results confirmed that the combination therapy of B. longum 2165 and IFN-α induced significantly higher IFN-γ secretion, higher population of CD4 + T and CD8 + T cells secreting IFN-γ, and higher CTL activity against EL4-NS3/4A cells compared with the control groups of phosphate-buffered saline, B. longum 2165 alone, and IFN-α alone (p < 0.05). We also confirmed that the combination therapy strongly enhanced tumor growth inhibitory effects in vivo with no serious adverse effects (p < 0.05). These results suggest that the combination of B. longum 2165 and IFN-α could induce a strong cellular immunity specific to NS3 protein as a combination therapy augmenting the current SOC immunotherapy against chronic HCV infection.

Level of UV-B radiation influences the effects of glyphosate-based herbicide on the spotted salamander.

PubMed

Levis, Nicholas A; Johnson, Jarrett R

2015-07-01

Glyphosate-based herbicides are the number one pesticide in the United States and are used commonly around the world. Understanding the affects of glyphosate-based herbicides on non-target wildlife, for example amphibians, is critical for evaluation of regulations pertaining to the use of such herbicides. Additionally, it is important to understand how variation in biotic and abiotic environmental conditions, such as UV-B light regime, could potentially affect how glyphosate-based herbicides interact with non-target species. This study used artificial pond mesocosms to identify the effects of generic glyphosate-based herbicide (GLY-4 Plus) on mortality, cellular immune response, body size, and morphological plasticity of larvae of the spotted salamander (Ambystoma maculatum) under conditions that reflect moderate (UV(M)) and low (UV(L)) UV-B light regimes. Survival within a given UV-B level was unaffected by herbicide presence or absence. However, when herbicide was present, survival varied between UV-B levels with higher survival in UV(M) conditions. Herbicide presence in the UV(M) treatments also decreased body size and reduced cellular immune response. In the UV(L) treatments, the presence of herbicide increased body size and affected tail morphology. Finally, in the absence of herbicide, body size and cellular immune response were higher in UV(M) treatments compared to UV(L) treatments. Thus, the effects of herbicide on salamander fitness were dependent on UV-B level. As anthropogenic habitat modifications continue to alter landscapes that contain amphibian breeding ponds, salamanders may increasingly find themselves in locations with reduced canopy cover and increased levels of UV light. Our findings suggest that the probability of surviving exposure to the glyphosate-based herbicide used in this study may be elevated in more open canopy ponds, but the effects on other components of fitness may be varied and unexpected.

Benznidazole, the trypanocidal drug used for Chagas disease, induces hepatic NRF2 activation and attenuates the inflammatory response in a murine model of sepsis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lambertucci, Flavia

Molecular mechanisms on sepsis progression are linked to the imbalance between reactive oxygen species (ROS) production and cellular antioxidant capacity. Previous studies demonstrated that benznidazole (BZL), known for its antiparasitic action on Trypanosoma cruzi, has immunomodulatory effects, increasing survival in C57BL/6 mice in a model of polymicrobial sepsis induced by cecal ligation and puncture (CLP). The mechanism by which BZL inhibits inflammatory response in sepsis is poorly understood. Also, our group recently reported that BZL is able to activate the nuclear factor erytroide-derived 2-Like 2 (NRF2) in vitro. The aim of the present work was to delineate the beneficial rolemore » of BZL during sepsis, analyzing its effects on the cellular redox status and the possible link to the innate immunity receptor TLR4. Specifically, we analyzed the effect of BZL on Nrf2 regulation and TLR4 expression in liver of mice 24 hours post-CLP. BZL was able to induce NRF2 nuclear protein localization in CLP mice. Also, we found that protein kinase C (PKC) is involved in the NRF2 nuclear accumulation and induction of its target genes. In addition, BZL prompted a reduction in hepatic CLP-induced TLR4 protein membrane localization, evidencing its immunomodulatory effects. Together, our results demonstrate that BZL induces hepatic NRF2 activation with the concomitant increase in the antioxidant defenses, and the attenuation of inflammatory response, in part, by inhibiting TLR4 expression in a murine model of sepsis. - Highlights: • BZL improves survival rate after polymicrobial sepsis • BZL enhances hepatic NRF2 nuclear accumulation in a model of sepsis, in part, by a mechanism dependent on PKC activation • BZL-enhanced NRF2 induction regulates antioxidant enzymes and increases antioxidant cellular defenses in sepsis • BZL blocks liver ROS production and ROS-induced TLR4 plasma membrane expression in septic mice.« less

Curcuminoid Binding to Embryonal Carcinoma Cells: Reductive Metabolism, Induction of Apoptosis, Senescence, and Inhibition of Cell Proliferation

PubMed Central

Quitschke, Wolfgang W.

2012-01-01

Curcumin preparations typically contain a mixture of polyphenols, collectively referred to as curcuminoids. In addition to the primary component curcumin, they also contain smaller amounts of the co-extracted derivatives demethoxycurcumin and bisdemethoxycurcumin. Curcuminoids can be differentially solubilized in serum, which allows for the systematic analysis of concentration-dependent cellular binding, biological effects, and metabolism. Technical grade curcumin was solubilized in fetal calf serum by two alternative methods yielding saturated preparations containing either predominantly curcumin (60%) or bisdemethoxycurcumin (55%). Continual exposure of NT2/D1 cells for 4–6 days to either preparation in cell culture media reduced cell division (1–5 µM), induced senescence (6–7 µM) or comprehensive cell death (8–10 µM) in a concentration-dependent manner. Some of these effects could also be elicited in cells transiently exposed to higher concentrations of curcuminoids (47 µM) for 0.5–4 h. Curcuminoids induced apoptosis by generalized activation of caspases but without nucleosomal fragmentation. The equilibrium binding of serum-solubilized curcuminoids to NT2/D1 cells incubated with increasing amounts of curcuminoid-saturated serum occurred with apparent overall dissociation constants in the 6–10 µM range. However, the presence of excess free serum decreased cellular binding in a hyperbolic manner. Cellular binding was overwhelmingly associated with membrane fractions and bound curcuminoids were metabolized in NT2/D1 cells via a previously unidentified reduction pathway. Both the binding affinities for curcuminoids and their reductive metabolic pathways varied in other cell lines. These results suggest that curcuminoids interact with cellular binding sites, thereby activating signal transduction pathways that initiate a variety of biological responses. The dose-dependent effects of these responses further imply that distinct cellular pathways are sequentially activated and that this activation is dependent on the affinity of curcuminoids for the respective binding sites. Defined serum-solubilized curcuminoids used in cell culture media are thus suitable for further investigating the differential activation of signal transduction pathways. PMID:22768090

Synthetic tambjamine analogues induce mitochondrial swelling and lysosomal dysfunction leading to autophagy blockade and necrotic cell death in lung cancer.

PubMed

Rodilla, Ananda M; Korrodi-Gregório, Luís; Hernando, Elsa; Manuel-Manresa, Pilar; Quesada, Roberto; Pérez-Tomás, Ricardo; Soto-Cerrato, Vanessa

2017-02-15

Current pharmacological treatments for lung cancer show very poor clinical outcomes, therefore, the development of novel anticancer agents with innovative mechanisms of action is urgently needed. Cancer cells have a reversed pH gradient compared to normal cells, which favours cancer progression by promoting proliferation, metabolic adaptation and evasion of apoptosis. In this regard, the use of ionophores to modulate intracellular pH appears as a promising new therapeutic strategy. Indeed, there is a growing body of evidence supporting ionophores as novel antitumour drugs. Despite this, little is known about the implications of pH deregulation and homeostasis imbalance triggered by ionophores at the cellular level. In this work, we deeply analyse for the first time the anticancer effects of tambjamine analogues, a group of highly effective anion selective ionophores, at the cellular and molecular levels. First, their effects on cell viability were determined in several lung cancer cell lines and patient-derived cancer stem cells, demonstrating their potent cytotoxic effects. Then, we have characterized the induced lysosomal deacidification, as well as, the massive cytoplasmic vacuolization observed after treatment with these compounds, which is consistent with mitochondrial swelling. Finally, the activation of several proteins involved in stress response, autophagy and apoptosis was also detected, although they were not significantly responsible for the cell death induced. Altogether, these evidences suggest that tambjamine analogues provoke an imbalance in cellular ion homeostasis that triggers mitochondrial dysfunction and lysosomal deacidification leading to a potent cytotoxic effect through necrosis in lung cancer cell lines and cancer stem cells. Copyright © 2016 Elsevier Inc. All rights reserved.

Industrial grade 2D molybdenum disulphide (MoS2): an in vitro exploration of the impact on cellular uptake, cytotoxicity, and inflammation

NASA Astrophysics Data System (ADS)

Moore, Caroline; Movia, Dania; Smith, Ronan J.; Hanlon, Damien; Lebre, Filipa; Lavelle, Ed C.; Byrne, Hugh J.; Coleman, Jonathan N.; Volkov, Yuri; McIntyre, Jennifer

2017-06-01

The recent surge in graphene research, since its liquid phase monolayer isolation and characterization in 2004, has led to advancements which are accelerating the exploration of alternative 2D materials such as molybdenum disulphide (MoS2), whose unique physico-chemical properties can be exploited in applications ranging from cutting edge electronic devices to nanomedicine. However, to assess any potential impact on human health and the environment, the need to understand the bio-interaction of MoS2 at a cellular and sub-cellular level is critical. Notably, it is important to assess such potential impacts of materials which are produced by large scale production techniques, rather than research grade materials. The aim of this study was to explore cytotoxicity, cellular uptake and inflammatory responses in established cell-lines that mimic different potential exposure routes (inhalation, A549; ingestion, AGS; monocyte, THP-1) following incubation with MoS2 flakes of varying sizes (50 nm, 117 nm and 177 nm), produced by liquid phase exfoliation. Using high content screening (HCS) and Live/Dead assays, it was established that 1 µg ml-1 (for the three different MoS2 sizes) did not induce toxic effects on any of the cell-lines. Confocal microscopy images revealed a normal cellular morphology in all cases. Transmission electron microscopy (TEM) confirmed the uptake of all MoS2 nanomaterials in all the cell-lines, the MoS2 ultimately locating in single membrane vesicles. At such sub-lethal doses, inflammatory responses are observed, however, associated, at least partially, with the presence of lipopolysaccharide endotoxin in nanomaterial suspensions and surfactant samples. Therefore, the inflammatory response of the cells to the MoS2 or endotoxin contamination was interrogated using a 10-plex ELISA which illustrates cytokine production. The experiments carried out using wild-type and endotoxin hyporesponsive bone marrow derived dendritic cells confirmed that the inflammatory responses result from a combination of endotoxin contamination, the MoS2 nanomaterials themselves, and the stabilizing surfactant.

Assessment of the Risks from Imbedded Fragments of Depleted Uranium

DTIC Science & Technology

1993-03-01

for chronic kidney toxicity; the impact of fibrotic encapsulation , if it occurs; and the chemical form of the imbedded fragment. The potential for...Effects of Depleted Uranium Imbedded in Tissue Reference: Brigadier General Ronald R. Blanck (SGPS-PSP) letter of 26 February 1992 In response to your...the muscle and fatty tissue will probably occur and will occur in all other tissue types that elicit similar cellular responses to foreign bodies. It

Changes in lymphocyte accumulation and proliferation in the lymph nodes draining the pregnant uterus.

PubMed Central

Ansell, J D; McDougall, C M; Speedy, G; Inchley, C J

1978-01-01

Changes in weight, lymphocyte accumulation and cellular proliferation have been measured in the lymph nodes draining the uterus during inter- and intra-strain pregnancies and compared with similar effects after other antigenic stimuli. From the data obtained it was concluded that "paternal" antigenic stimulation from the conceptus initiated an immune response in these nodes. The mechanisms of the subsequent suppression of this response are discussed. PMID:657586

Cellular response to low dose radiation: Role of phosphatidylinositol-3 kinase like kinases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Balajee, A.S.; Meador, J.A.; Su, Y.

It is increasingly realized that human exposure either to an acute low dose or multiple chronic low doses of low LET radiation has the potential to cause different types of cancer. Therefore, the central theme of research for DOE and NASA is focused on understanding the molecular mechanisms and pathways responsible for the cellular response to low dose radiation which would not only improve the accuracy of estimating health risks but also help in the development of predictive assays for low dose radiation risks associated with tissue degeneration and cancer. The working hypothesis for this proposal is that the cellularmore » mechanisms in terms of DNA damage signaling, repair and cell cycle checkpoint regulation are different for low and high doses of low LET radiation and that the mode of action of phosphatidylinositol-3 kinase like kinases (PIKK: ATM, ATR and DNA-PK) determines the dose dependent cellular responses. The hypothesis will be tested at two levels: (I) Evaluation of the role of ATM, ATR and DNA-PK in cellular response to low and high doses of low LET radiation in simple in vitro human cell systems and (II) Determination of radiation responses in complex cell microenvironments such as human EpiDerm tissue constructs. Cellular responses to low and high doses of low LET radiation will be assessed from the view points of DNA damage signaling, DNA double strand break repair and cell cycle checkpoint regulation by analyzing the activities (i.e. post-translational modifications and kinetics of protein-protein interactions) of the key target proteins for PI-3 kinase like kinases both at the intra-cellular and molecular levels. The proteins chosen for this proposal are placed under three categories: (I) sensors/initiators include ATM ser1981, ATR, 53BP1, gamma-H2AX, MDC1, MRE11, Rad50 and Nbs1; (II) signal transducers include Chk1, Chk2, FANCD2 and SMC1; and (III) effectors include p53, CDC25A and CDC25C. The primary goal of this proposal is to elucidate the differences in cellular defense mechanisms between low and high doses of low LET radiation and to define the radiation doses where the cellular DNA damage signaling and repair mechanisms tend to shift. This information is critically important to address and advance some of the low dose research program objectives of DOE. The results of this proposed study will lead to a better understanding of the mechanisms for the cellular responses to low and high doses of low LET radiation. Further, systematic analysis of the role of PIKK signaling pathways as a function of radiation dose in tissue microenvironment will provide useful mechanistic information for improving the accuracy of radiation risk assessment for low doses. Knowledge of radiation responses in tissue microenvironment is important for the accurate prediction of ionizing radiation risks associated with cancer and tissue degeneration in humans.« less

WE-DE-202-00: Connecting Radiation Physics with Computational Biology

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

Radiation therapy for the treatment of cancer has been established as a highly precise and effective way to eradicate a localized region of diseased tissue. To achieve further significant gains in the therapeutic ratio, we need to move towards biologically optimized treatment planning. To achieve this goal, we need to understand how the radiation-type dependent patterns of induced energy depositions within the cell (physics) connect via molecular, cellular and tissue reactions to treatment outcome such as tumor control and undesirable effects on normal tissue. Several computational biology approaches have been developed connecting physics to biology. Monte Carlo simulations are themore » most accurate method to calculate physical dose distributions at the nanometer scale, however simulations at the DNA scale are slow and repair processes are generally not simulated. Alternative models that rely on the random formation of individual DNA lesions within one or two turns of the DNA have been shown to reproduce the clusters of DNA lesions, including single strand breaks (SSBs), double strand breaks (DSBs) without the need for detailed track structure simulations. Efficient computational simulations of initial DNA damage induction facilitate computational modeling of DNA repair and other molecular and cellular processes. Mechanistic, multiscale models provide a useful conceptual framework to test biological hypotheses and help connect fundamental information about track structure and dosimetry at the sub-cellular level to dose-response effects on larger scales. In this symposium we will learn about the current state of the art of computational approaches estimating radiation damage at the cellular and sub-cellular scale. How can understanding the physics interactions at the DNA level be used to predict biological outcome? We will discuss if and how such calculations are relevant to advance our understanding of radiation damage and its repair, or, if the underlying biological processes are too complex for a mechanistic approach. Can computer simulations be used to guide future biological research? We will debate the feasibility of explaining biology from a physicists’ perspective. Learning Objectives: Understand the potential applications and limitations of computational methods for dose-response modeling at the molecular, cellular and tissue levels Learn about mechanism of action underlying the induction, repair and biological processing of damage to DNA and other constituents Understand how effects and processes at one biological scale impact on biological processes and outcomes on other scales J. Schuemann, NCI/NIH grantsS. McMahon, Funding: European Commission FP7 (grant EC FP7 MC-IOF-623630)« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

McMahon, S.

Radiation therapy for the treatment of cancer has been established as a highly precise and effective way to eradicate a localized region of diseased tissue. To achieve further significant gains in the therapeutic ratio, we need to move towards biologically optimized treatment planning. To achieve this goal, we need to understand how the radiation-type dependent patterns of induced energy depositions within the cell (physics) connect via molecular, cellular and tissue reactions to treatment outcome such as tumor control and undesirable effects on normal tissue. Several computational biology approaches have been developed connecting physics to biology. Monte Carlo simulations are themore » most accurate method to calculate physical dose distributions at the nanometer scale, however simulations at the DNA scale are slow and repair processes are generally not simulated. Alternative models that rely on the random formation of individual DNA lesions within one or two turns of the DNA have been shown to reproduce the clusters of DNA lesions, including single strand breaks (SSBs), double strand breaks (DSBs) without the need for detailed track structure simulations. Efficient computational simulations of initial DNA damage induction facilitate computational modeling of DNA repair and other molecular and cellular processes. Mechanistic, multiscale models provide a useful conceptual framework to test biological hypotheses and help connect fundamental information about track structure and dosimetry at the sub-cellular level to dose-response effects on larger scales. In this symposium we will learn about the current state of the art of computational approaches estimating radiation damage at the cellular and sub-cellular scale. How can understanding the physics interactions at the DNA level be used to predict biological outcome? We will discuss if and how such calculations are relevant to advance our understanding of radiation damage and its repair, or, if the underlying biological processes are too complex for a mechanistic approach. Can computer simulations be used to guide future biological research? We will debate the feasibility of explaining biology from a physicists’ perspective. Learning Objectives: Understand the potential applications and limitations of computational methods for dose-response modeling at the molecular, cellular and tissue levels Learn about mechanism of action underlying the induction, repair and biological processing of damage to DNA and other constituents Understand how effects and processes at one biological scale impact on biological processes and outcomes on other scales J. Schuemann, NCI/NIH grantsS. McMahon, Funding: European Commission FP7 (grant EC FP7 MC-IOF-623630)« less

WE-DE-202-01: Connecting Nanoscale Physics to Initial DNA Damage Through Track Structure Simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schuemann, J.

Radiation therapy for the treatment of cancer has been established as a highly precise and effective way to eradicate a localized region of diseased tissue. To achieve further significant gains in the therapeutic ratio, we need to move towards biologically optimized treatment planning. To achieve this goal, we need to understand how the radiation-type dependent patterns of induced energy depositions within the cell (physics) connect via molecular, cellular and tissue reactions to treatment outcome such as tumor control and undesirable effects on normal tissue. Several computational biology approaches have been developed connecting physics to biology. Monte Carlo simulations are themore » most accurate method to calculate physical dose distributions at the nanometer scale, however simulations at the DNA scale are slow and repair processes are generally not simulated. Alternative models that rely on the random formation of individual DNA lesions within one or two turns of the DNA have been shown to reproduce the clusters of DNA lesions, including single strand breaks (SSBs), double strand breaks (DSBs) without the need for detailed track structure simulations. Efficient computational simulations of initial DNA damage induction facilitate computational modeling of DNA repair and other molecular and cellular processes. Mechanistic, multiscale models provide a useful conceptual framework to test biological hypotheses and help connect fundamental information about track structure and dosimetry at the sub-cellular level to dose-response effects on larger scales. In this symposium we will learn about the current state of the art of computational approaches estimating radiation damage at the cellular and sub-cellular scale. How can understanding the physics interactions at the DNA level be used to predict biological outcome? We will discuss if and how such calculations are relevant to advance our understanding of radiation damage and its repair, or, if the underlying biological processes are too complex for a mechanistic approach. Can computer simulations be used to guide future biological research? We will debate the feasibility of explaining biology from a physicists’ perspective. Learning Objectives: Understand the potential applications and limitations of computational methods for dose-response modeling at the molecular, cellular and tissue levels Learn about mechanism of action underlying the induction, repair and biological processing of damage to DNA and other constituents Understand how effects and processes at one biological scale impact on biological processes and outcomes on other scales J. Schuemann, NCI/NIH grantsS. McMahon, Funding: European Commission FP7 (grant EC FP7 MC-IOF-623630)« less

The dominant roles of ICAM-1-encoding gene in DNA vaccination against Japanese encephalitis virus are the activation of dendritic cells and enhancement of cellular immunity.

PubMed

Zhai, Yong-Zhen; Zhou, Yan; Ma, Li; Feng, Guo-He

2013-01-01

We investigated the cellular immune responses elicited by a plasmid DNA vaccine encoding prM-E protein from the Japanese encephalitis (JE) virus (JEV) with or without various forms of intercellular adhesion molecule (ICAM)-1 gene to maximize the immune responses evoked by the JE DNA vaccine. We observed that co-immunization with the construct containing murine ICAM-1 gene (pICAM-1) resulted in a significant increase in the percentage of CD4(+)T cells, high level of JEV-specific cytotoxic T lymphocyte response, and high production of T helper 1 (Th1)-type cytokines in splenic T cells. Furthermore, the co-expression of ICAM-1 and DNA immunogens was found to be more effective in generating T cell-mediated immune responses than those induced by immunization with pJME in combination with pICAM-1. Our results suggested that ICAM-1 enhanced T cell receptor signaling and activated Th1 immune responses in the JEV model system by increasing the induction of CD4(+)Th1 cell subset and activating dendritic cells. Copyright © 2013 Elsevier Inc. All rights reserved.

Subcellular fractions of Brucella ovis distinctively induce the production of interleukin-2, interleukin-4, and interferon-γ in mice

PubMed Central

2005-01-01

Abstract The aim of this study was to evaluate the effect of 3 Brucella ovis subcellular protein fractions: Outer membrane (OMP), inner membrane (IMP), and cytoplasm (CP), on cellular immune response by in vitro production of interleukin (IL)-2, IL-4, and interferon (IFN)-γ. Each fraction was inoculated 3 times into Balb/c mice, primary cultures of mice spleen cells were done, and these were then stimulated with the fractions. Culture supernatants were collected at 24, 48, 72, 96, and 120 h postinoculation. Cytokine concentration was measured by Duoset-enzyme-linked immunosorbent assay (ELISA). The OMP fraction induced highest cellular immune response of 1000 pg/mL of IL-2 at 24 h, which decreased to < 100 pg/mL by 96 h. The IL-2 response for the IMP fraction was low at 24 h, but exceeded that of the OMP fraction at 72, 96, and 120 h. The CP showed a poor IL response. Regarding the IFN-γ production, OMP and IMP induced a high response at 120 h. These results open the possibility for the use of B. ovis outer and inner membrane proteins as a subcellular vaccine. PMID:15745223

A preparation for studying electrical stimulation of the retina in vivo in rat

NASA Astrophysics Data System (ADS)

Baig-Silva, M. S.; Hathcock, C. D.; Hetling, J. R.

2005-03-01

A remaining challenge to the development of electronic prostheses for vision is improving the effectiveness of retinal stimulation. Electrode design and stimulus parameters need to be optimized such that the neural output from the retina conveys information to the mind's eye that aids the patient in interpreting his or her environment. This optimization will require a detailed understanding of the response of the retina to electrical stimulation. The identity and response characteristics of the cellular targets of stimulation need to be defined and evaluated. Described here is an in vivo preparation for studying electrical stimulation of the retina in rat at the cellular level. The use of rat makes available a number of well-described models of retinal disease that motivate prosthesis development. Artificial stimulation can be investigated by adapting techniques traditionally employed to study the response of the retina to photic stimuli, such as recording at the cornea, single-cell recording, and pharmacological dissection of the response. Pilot studies include amplitude-intensity response data for subretinal and transretinal stimulation paradigms recorded in wild-type rats and a transgenic rat model of autosomal dominant retinitis pigmentosa. The ability to record single-unit ganglion cell activity in vivo is also demonstrated.

Transcranial amelioration of inflammation and cell death after brain injury

NASA Astrophysics Data System (ADS)

Roth, Theodore L.; Nayak, Debasis; Atanasijevic, Tatjana; Koretsky, Alan P.; Latour, Lawrence L.; McGavern, Dorian B.

2014-01-01

Traumatic brain injury (TBI) is increasingly appreciated to be highly prevalent and deleterious to neurological function. At present, no effective treatment options are available, and little is known about the complex cellular response to TBI during its acute phase. To gain insights into TBI pathogenesis, we developed a novel murine closed-skull brain injury model that mirrors some pathological features associated with mild TBI in humans and used long-term intravital microscopy to study the dynamics of the injury response from its inception. Here we demonstrate that acute brain injury induces vascular damage, meningeal cell death, and the generation of reactive oxygen species (ROS) that ultimately breach the glial limitans and promote spread of the injury into the parenchyma. In response, the brain elicits a neuroprotective, purinergic-receptor-dependent inflammatory response characterized by meningeal neutrophil swarming and microglial reconstitution of the damaged glial limitans. We also show that the skull bone is permeable to small-molecular-weight compounds, and use this delivery route to modulate inflammation and therapeutically ameliorate brain injury through transcranial administration of the ROS scavenger, glutathione. Our results shed light on the acute cellular response to TBI and provide a means to locally deliver therapeutic compounds to the site of injury.

Functionally Charged Polystyrene Particles Activate Immortalized Mouse Microglia (BV2): Cellular and Genomic Response

EPA Science Inventory

The effect of particle surface charge on the biological activation of immortalized mouse microglia (BV2) was examined. Same size (~850-950 nm) spherical polystyrene microparticles (SPM) with net negative (carboxyl, COOH-) or positive (dimethyl amino, CH₃)₂

Finding Toxicological Tipping Points from High-Content Imaging Data (WC10)

EPA Science Inventory

A key challenge to using in vitro data in risk assessment is differentiating between chemical-induced adaptive versus adverse cellular responses. To further investigate this issue, we studied the effects of hundreds of chemicals in HepG2 cells using high-content imaging (HCI). HC...

The effect of pegylated granulocyte colony stimulating factor treatment prior to experimental mastitis in lactating Holsteins

USDA-ARS?s Scientific Manuscript database

Mastitis continues to lead health and economic concerns for the dairy industry. Better understanding of dairy cattle's response to pathogens is important for development of next-generation antibiotic alternatives. Neutrophils are the first-acting, most prominent, cellular defense against mastitis ca...

Biomaterials for tissue engineering: summary

NASA Technical Reports Server (NTRS)

Christenson, L.; Mikos, A. G.; Gibbons, D. F.; Picciolo, G. L.; McIntire, L. V. (Principal Investigator)

1997-01-01

This article summarizes presentations and discussion at the workshop "Enabling Biomaterial Technology for Tissue Engineering," which was held during the Fifth World Biomaterials Congress in May 1996. Presentations covered the areas of material substrate architecture, barrier effects, and cellular response, including analysis of biomaterials challenges involved in producing specific tissue-engineered products.

Computational membrane biophysics: From ion channel interactions with drugs to cellular function.

PubMed

Miranda, Williams E; Ngo, Van A; Perissinotti, Laura L; Noskov, Sergei Yu

2017-11-01

The rapid development of experimental and computational techniques has changed fundamentally our understanding of cellular-membrane transport. The advent of powerful computers and refined force-fields for proteins, ions, and lipids has expanded the applicability of Molecular Dynamics (MD) simulations. A myriad of cellular responses is modulated through the binding of endogenous and exogenous ligands (e.g. neurotransmitters and drugs, respectively) to ion channels. Deciphering the thermodynamics and kinetics of the ligand binding processes to these membrane proteins is at the heart of modern drug development. The ever-increasing computational power has already provided insightful data on the thermodynamics and kinetics of drug-target interactions, free energies of solvation, and partitioning into lipid bilayers for drugs. This review aims to provide a brief summary about modeling approaches to map out crucial binding pathways with intermediate conformations and free-energy surfaces for drug-ion channel binding mechanisms that are responsible for multiple effects on cellular functions. We will discuss post-processing analysis of simulation-generated data, which are then transformed to kinetic models to better understand the molecular underpinning of the experimental observables under the influence of drugs or mutations in ion channels. This review highlights crucial mathematical frameworks and perspectives on bridging different well-established computational techniques to connect the dynamics and timescales from all-atom MD and free energy simulations of ion channels to the physiology of action potentials in cellular models. This article is part of a Special Issue entitled: Biophysics in Canada, edited by Lewis Kay, John Baenziger, Albert Berghuis and Peter Tieleman. Copyright © 2017 Elsevier B.V. All rights reserved.

A scientific role for Space Station Freedom: Research at the cellular level

NASA Technical Reports Server (NTRS)

Johnson, Terry C.; Brady, John N.

1993-01-01

The scientific importance of Space Station Freedom is discussed in light of the valuable information that can be gained in cellular and developmental biology with regard to the microgravity environment on the cellular cytoskeleton, cellular responses to extracellular signal molecules, morphology, events associated with cell division, and cellular physiology. Examples of studies in basic cell biology, as well as their potential importance to concerns for future enabling strategies, are presented.

Mitochondrial correlates of signaling processes involved with the cellular response to eimeria infection in broiler chickens

USDA-ARS?s Scientific Manuscript database

Host cellular responses to coccidiosis infection are consistent with elements of apoptosis, autophagy, and necrosis. These processes are enhanced in the cell through cell-directed signaling or repressed through parasite-derived inhibitors of these processes favoring the survival of the parasite. Acr...

Effects of long-term hypergravity on growth of Arabidopsis seedlings

NASA Astrophysics Data System (ADS)

Karahara, Ichirou; Ando, Naoko; Tamaoki, Daisuke; Kamisaka, Seiichiro

Effects of altered gravity on growth of plant root are not yet well understood compared to that of shoot organ such as stem, epicotyl or hypocotyl. And besides, its effect on growth is not yet examined at cellular level either in the root or the shoot. In the present study, we examined effects of long-term hypergravity on growth not only of the root but also the shoot at cellular level. Seeds of Arabidopsis were sown on gelrite containing Murashige-Skoog medium and were started to be exposed to hypergravity before germination. Growth of the hypocotyl had been inhibited since 3 d after the onset of hypergravity treatment at both 100 and 300 G while that of the root was not at either gravity. Longitudinal length of epidermal cells in one cell file decreased in response to hypergravity at 300 G in 3 d old hypocotyls while the number of the epidermal cells did not.

Tissue response to intraperitoneal implants of polyethylene oxide-modified polyethylene terephthalate.

PubMed

Desai, N P; Hubbell, J A

1992-01-01

Polyethylene terephthalate films surface modified with polyethylene oxide of mol wt 18,500 g/mol (18.5 k) by a previously described technique, were implanted in the peritoneal cavity of mice, along with their respective untreated controls, for periods of 1-28 d. The implants were retrieved and examined for tissue reactivity and cellular adherence. The control polyethylene terephthalate surfaces showed an initial inflammatory reaction followed by an extensive fibrotic response with a mean thickness of 60 microns at 28 d. By contrast, polyethylene oxide-modified polyethylene terephthalate showed only a mild inflammatory response and no fibrotic encapsulation throughout the implantation period: at 28 d a cellular monolayer was observed. Apparently either the polyethylene oxide-modified surface was stimulating less inflammation, which was in turn stimulating less fibroblastic overgrowth, or the cellular adhesion to the polyethylene oxide-modified surface was too weak to support cellular multilayers.

HIV-associated cellular senescence: A contributor to accelerated aging.

PubMed

Cohen, Justin; Torres, Claudio

2017-07-01

Due to the advent of antiretroviral therapy HIV is no longer a terminal disease and the HIV infected patients are becoming increasingly older. While this is a major success, with increasing age comes an increased risk for disease. The age-related comorbidities that HIV infected patients experience suggest that they suffer from accelerated aging. One possible contributor to this accelerated aging is cellular senescence, an age-associated response that can occur prematurely in response to stress, and that is emerging as a contributor to disease and aging. HIV patients experience several stressors such as the virus itself, antiretroviral drugs and to a lesser extent, substance abuse that can induce cellular senescence. This review summarizes the current knowledge of senescence induction in response to these stressors and their relation to the comorbidities in HIV patients. Cellular senescence may be a possible therapeutic target for these comorbidities. Copyright © 2016 Elsevier B.V. All rights reserved.

Haemolytic activities and adjuvant effect of Anemone raddeana saponins (ARS) on the immune responses to ovalbumin in mice.

PubMed

Sun, Yongxu; Li, Mingquan; Liu, Jicheng

2008-08-01

In this study, saponins (ARS) extracted from the rhizoma of Anemone raddeana were evaluated for their haemolytic activities and its potential ability as adjuvant on the cellular and humoral immune responses of ICR mice against ovalbumin. The haemolytic activity of ARS was determined using 0.5% rabbit red blood cell. ARS showed a slight haemolytic effect, with its haemolytic percents being 16.50 and 3.56% at the concentrations of 500 and 250 microg/ml, respectively. ICR mice were immunized subcutaneously with OVA 100 microg alone or with OVA 100 mug dissolved in saline containing Alum (200 microg), QuilA (10 and 20 microg) or ARS (50, 100 or 200 microg) on Days 1 and 15. Two weeks later (Day 28), concanavalin A (Con A)-, lipopolysaccharide (LPS)- and OVA-stimulated splenocyte proliferation and OVA-specific antibodies in serum were measured. ARS significantly enhanced the Con A-, LPS-, and OVA-induced splenocyte proliferation in the OVA-immunized mice especially at a dose of 100 microg (P<0.01 or P<0.05). The OVA-specific IgG, IgG1 and IgG2b antibody levels in serum were also significantly enhanced by ARS compared with OVA control group (P<0.01 or P<0.05). Moreover, no significant differences (P>0.05) were observed between enhancing effect of ARS and QuilA on the OVA-specific IgG2b antibody responses to OVA in mice. The results suggest that ARS showed a slight haemolytic effect and enhanced significantly a specific antibody and cellular response against OVA in mice.

Pseudolaric acid B attenuates atherosclerosis progression and inflammation by suppressing PPARγ-mediated NF-κB activation.

PubMed

Li, Tan; Wang, Wei; Li, Yu-Xiu; Li, Xiao; Ji, Wen-Jie; Ma, Yong-Qiang; Chen, Hong; Zhao, Ji-Hong; Zhou, Xin

2018-06-01

Atherosclerosis is a progressive disease of large arteries characterized with chronic inflammation and aberrant immune response. Pseudolaric acid B (PB) has been found to exert multiple effects by inhibiting inflammatory response. However, there is no comprehensive assessment of the effects of PB on atherosclerosis using relevant in vivo and in vitro models. Male ApoE -/- mice were treated with PB orally with a high fat diet (HFD) to clarify its anti-atherosclerotic activities. RAW264.7 macrophage line, a well-accepted cell model of atherosclerosis, was used to investigate anti-inflammatory effects and molecular mechanisms of PB. PB significantly attenuated atherosclerotic lesions by modulating plasma lipid profiles as well as inhibiting inflammatory responses in macrophages of atherosclerotic mice. Meanwhile, PB markedly suppressed the expression of pro-inflammatory cytokines, and regulated cholesterol efflux related genes in oxidative low density lipoprotein (ox-LDL)-loaded macrophages. The cellular uptake of Dil-labeled ox-LDL was significantly inhibited by PB either. Moreover, the ability of PB to suppress nuclear factor kappa B (NF-κB) and activate peroxisome proliferator-activated receptor gamma (PPARγ) was confirmed using luciferase reporter assays. Conversely, the selective PPARγ antagonist GW9662 reversed the influence of PB in macrophages. Together, these findings indicate that PB exerts its protective effects on atherosclerosis by inhibiting macrophage-mediated inflammatory response and cellular ox-LDL uptake, and promoting cholesterol efflux by suppressing NF-κB activation PPARγ-dependently. Therefore, PB may be a promising agent for inflammatory and atherosclerotic diseases. Copyright © 2018. Published by Elsevier B.V.

Haemoglobin function in vertebrates: evolutionary changes in cellular regulation in hypoxia.

PubMed

Nikinmaa, M

2001-11-15

The evolution of erythrocytic hypoxia responses is reviewed by comparing the cellular control of haemoglobin-oxygen affinity in agnathans, teleost fish and terrestrial vertebrates. The most ancient response to hypoxic conditions appears to be an increase in cell volume, which increases the haemoglobin-oxygen affinity in lampreys. In teleost fish, an increase of cell volume in hypoxic conditions is also evident. The volume increase is coupled to an increase in erythrocyte pH. These changes are caused by an adrenergic activation of sodium/proton exchange across the erythrocyte membrane. The mechanism is important in acute hypoxia and is followed by a decrease in cellular adenosine triphosphate (ATP) and guanosine triphosphate (GTP) concentrations in continued hypoxia. In hypoxic bird embryos, the ATP levels are also reduced. The mechanisms by which hypoxia decreases cellular ATP and GTP concentrations remains unknown, although at least in bird embryos cAMP-dependent mechanisms have been implicated. In mammals, hypoxia responses appear to occur mainly via modulation of cellular organic phosphate concentrations. In moderate hypoxia, 2,3-diphosphoglycerate levels are increased as a result of alkalosis caused by increased ventilation.

The Transcription Factor EB Links Cellular Stress to the Immune Response



PubMed Central

Nabar, Neel R.; Kehrl, John H.

2017-01-01

The transcription factor EB (TFEB) is the master transcriptional regulator of autophagy and lysosome biogenesis. Recent advances have led to a paradigm shift in our understanding of lysosomes from a housekeeping cellular waste bin to a dynamically regulated pathway that is efficiently turned up or down based on cellular needs. TFEB coordinates the cellular response to nutrient deprivation and other forms of cell stress through the lysosome system, and regulates a myriad of cellular processes associated with this system including endocytosis, phagocytosis, autophagy, and lysosomal exocytosis. Autophagy and the endolysosomal system are critical to both the innate and adaptive arms of the immune system, with functions in effector cell priming and direct pathogen clearance. Recent studies have linked TFEB to the regulation of the immune response through the endolysosmal pathway and by direct transcriptional activation of immune related genes. In this review, we discuss the current understanding of TFEB’s function and the molecular mechanisms behind TFEB activation. Finally, we discuss recent advances linking TFEB to the immune response that positions lysosomal signaling as a potential target for immune modulation. PMID:28656016

The Transcription Factor EB Links Cellular Stress to the Immune Response

.

PubMed

Nabar, Neel R; Kehrl, John H

2017-06-01

The transcription factor EB (TFEB) is the master transcriptional regulator of autophagy and lysosome biogenesis. Recent advances have led to a paradigm shift in our understanding of lysosomes from a housekeeping cellular waste bin to a dynamically regulated pathway that is efficiently turned up or down based on cellular needs. TFEB coordinates the cellular response to nutrient deprivation and other forms of cell stress through the lysosome system, and regulates a myriad of cellular processes associated with this system including endocytosis, phagocytosis, autophagy, and lysosomal exocytosis. Autophagy and the endolysosomal system are critical to both the innate and adaptive arms of the immune system, with functions in effector cell priming and direct pathogen clearance. Recent studies have linked TFEB to the regulation of the immune response through the endolysosmal pathway and by direct transcriptional activation of immune related genes. In this review, we discuss the current understanding of TFEB's function and the molecular mechanisms behind TFEB activation. Finally, we discuss recent advances linking TFEB to the immune response that positions lysosomal signaling as a potential target for immune modulation.

Ubiquitylation-dependent regulation of NEIL1 by Mule and TRIM26 is required for the cellular DNA damage response.

PubMed

Edmonds, Matthew J; Carter, Rachel J; Nickson, Catherine M; Williams, Sarah C; Parsons, Jason L

2017-01-25

Endonuclease VIII-like protein 1 (NEIL1) is a DNA glycosylase involved in initiating the base excision repair pathway, the major cellular mechanism for repairing DNA base damage. Here, we have purified the major E3 ubiquitin ligases from human cells responsible for regulation of NEIL1 by ubiquitylation. Interestingly, we have identified two enzymes that catalyse NEIL1 polyubiquitylation, Mcl-1 ubiquitin ligase E3 (Mule) and tripartite motif 26 (TRIM26). We demonstrate that these enzymes are capable of polyubiquitylating NEIL1 in vitro, and that both catalyse ubiquitylation of NEIL1 within the same C-terminal lysine residues. An siRNA-mediated knockdown of Mule or TRIM26 leads to stabilisation of NEIL1, demonstrating that these enzymes are important in regulating cellular NEIL1 steady state protein levels. Similarly, a mutant NEIL1 protein lacking residues for ubiquitylation is more stable than the wild type protein in vivo We also demonstrate that cellular NEIL1 protein is induced in response to ionising radiation (IR), although this occurs specifically in a Mule-dependent manner. Finally we show that stabilisation of NEIL1, particularly following TRIM26 siRNA, contributes to cellular resistance to IR. This highlights the importance of Mule and TRIM26 in maintaining steady state levels of NEIL1, but also those required for the cellular DNA damage response. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

Spaceflight and immune responses of Rhesus monkeys

NASA Technical Reports Server (NTRS)

Sonnenfeld, Gerald

1994-01-01

Evidence from both human and rodent studies indicates that alterations in immunological parameters occur after space flight. The objective of this project is to determine the effects of space flight on immune responses of Rhesus monkeys. The expected significance of the work is a determination of the range of immunological functions of the Rhesus monkey, a primate similar in many ways to man, affected by space flight. Changes in immune responses that could yield alterations in resistance to infection may be determined as well as the duration of alterations in immune responses. Additional information on the nature of cellular interactions for the generation of immune responses may also be obtained.

Novel function of Trim44 promotes an antiviral response by stabilizing VISA.

PubMed

Yang, Bo; Wang, Jie; Wang, Yanming; Zhou, Haiyan; Wu, Xiaodong; Tian, Zhigang; Sun, Bing

2013-04-01

Virus-induced signaling adaptor (VISA) functions as a critical adaptor in the regulation of both the production of type I IFNs and the subsequent control of the innate antiviral response. In this study, we demonstrate that tripartite motif (Trim)44 interacts with VISA and promotes VISA-mediated antiviral responses. The overexpression of Trim44 enhances the cellular response to viral infection, whereas Trim44 knockdown yields the opposite effect. Trim44 stabilizes VISA by preventing VISA ubiquitination and degradation. These findings suggest that Trim44 functions as a positive regulator of the virus-triggered immune response by enhancing the stability of VISA.

Dual effects exerted in vitro by micromolar concentrations of deoxynivalenol on undifferentiated caco-2 cells.

PubMed

Manda, Gina; Mocanu, Mihaela Andreea; Marin, Daniela Eliza; Taranu, Ionelia

2015-02-16

Contamination of crops used for food and feed production with Fusarium mycotoxins, such as deoxynivalenol (DON), raise important health and economic issues all along the food chain. Acute exposure to high DON concentrations can alter the intestinal barrier, while chronic exposure to lower doses may exert more subtle effects on signal transduction pathways, leading to disturbances in cellular homeostasis. Using real-time cellular impedance measurements, we studied the effects exerted in vitro by low concentrations of DON (0.37-1.50 μM), relevant for mycotoxin-contaminated food, on the proliferation of undifferentiated Caco-2 cells presenting a tumorigenic phenotype. A 1.5 μM concentration of DON maintained cell adherence of non-proliferating Caco-2 cells, whilst arresting the growth of actively proliferating cells compared with control Caco-2 cells in vitro. At 0.37 μM, DON enhanced Caco-2 cell metabolism, thereby triggering a moderate increase in cell proliferation. The results of the current study suggested that low concentrations of DON commonly detected in food may either limit or sustain the proliferation of colon cancer cells, depending on their proliferation status and on DON concentration. Soluble factors released by Lactobacillus strains can partially counteract the inhibitory action of DON on actively proliferating colon cancer cells. The study also emphasized that real-time cellular impedance measurements were a valuable tool for investigating the dynamics of cellular responses to xenobiotics.

Repeated exposure of mouse dermal fibroblasts at a sub-cytotoxic dose of UVB leads to premature senescence: a robust model of cellular photoaging.

PubMed

Zeng, Ji-ping; Bi, Bo; Chen, Liang; Yang, Ping; Guo, Yu; Zhou, Yi-qun; Liu, Tian-yi

2014-01-01

Photoaging skin is due to accumulative effect of UV irradiation that mainly imposes its damage on dermal fibroblasts. To mimic the specific cellular responses invoked by long term effect of UVB, it is preferable to develop a photo-damaged model in vitro based on repeated UVB exposure instead of a single exposure. To develop a photo-damaged model of fibroblasts by repeated UVB exposure allowing for investigation of molecular mechanism underlying premature senescence and testing of potential anti-photoaging compounds. Mouse dermal fibroblasts (MDFs) at early passages (passages 1-3) were exposed to a series of 4 sub-cytotoxic dose of UVB. The senescent phenotypes were detected at 24 or 48h after the last irradiation including cell viability, ROS generation, mitochondrial membrane potential, cell cycle, production and degradation of extracellular matrix. Repeated exposure of UVB resulted in remarkable features of senescence. It effectively avoided the disadvantages of single dose such as induction of cell death rather than senescence, inadequate stress resulting in cellular self-rehabilitation. Our work confirms the possibility of detecting cellular machinery that mediates UVB damage to fibroblasts in vitro by repeated exposure, while the potential molecular mechanisms including cell surface receptors, protein kinase signal transduction pathways, and transcription factors remain to be further evaluated. Copyright © 2013 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

Role of resveratrol in regulation of cellular defense systems against oxidative stress.

PubMed

Truong, Van-Long; Jun, Mira; Jeong, Woo-Sik

2018-01-01

Resveratrol, a natural polyphenolic compound, is found in various kinds of fruits, plants, and their commercial products such as red wine. It has been demonstrated to exhibit a variety of health-promoting effects including prevention and/or treatment of cardiovascular diseases, inflammation, diabetes, neurodegeneration, aging, and cancer. Cellular defensive properties of resveratrol can be explained through its ability of either directly neutralizing reactive oxygen species/reactive nitrogen species (ROS/RNS) or indirectly upregulating the expression of cellular defensive genes. As a direct antioxidant agent, resveratrol scavenges diverse ROS/RNS as well as secondary organic radicals with mechanisms of hydrogen atom transfer and sequential proton loss electron transfer, thereby protecting cellular biomolecules from oxidative damage. Resveratrol also enhances the expression of various antioxidant defensive enzymes such as heme oxygenase 1, catalase, glutathione peroxidase, and superoxide dismutase as well as the induction of glutathione level responsible for maintaining the cellular redox balance. Such defenses could be achieved by regulating various signaling pathways including sirtuin 1, nuclear factor-erythroid 2-related factor 2 and nuclear factor κB. This review provides current understanding and information on the role of resveratrol in cellular defense system against oxidative stress. © 2017 BioFactors, 44(1):36-49, 2018. © 2017 International Union of Biochemistry and Molecular Biology.

Journey of Mesenchymal Stem Cells for Homing: Strategies to Enhance Efficacy and Safety of Stem Cell Therapy

PubMed Central

Kang, Sung Keun; Shin, Il Seob; Ko, Myung Soon; Jo, Jung Youn; Ra, Jeong Chan

2012-01-01

Human mesenchymal stem cells (MSCs) communicate with other cells in the human body and appear to “home” to areas of injury in response to signals of cellular damage, known as homing signals. This review of the state of current research on homing of MSCs suggests that favorable cellular conditions and the in vivo environment facilitate and are required for the migration of MSCs to the site of insult or injury in vivo. We review the current understanding of MSC migration and discuss strategies for enhancing both the environmental and cellular conditions that give rise to effective homing of MSCs. This may allow MSCs to quickly find and migrate to injured tissues, where they may best exert clinical benefits resulting from improved homing and the presence of increased numbers of MSCs. PMID:22754575

Accumulation and Effects of Organotin Compounds in Oysters and Mussels: Correlation with Serum Biochemical and Cytological Factors and Tissue Burdens

DTIC Science & Technology

1988-01-01

metallothioneins in the serum hemocytes of either bivalve. Responses by these animals to fatal or near fatal doses of TBT were thus very different from responses...Diego, CA 92110. USA N " IL -_ Dvsters and mussels exposed to a concentration of OTppb (g/liter) tributyltin from painted panels in fwin-g secivater accuu...doses of TBT were thus very different from responses to copper that we have reported elsewhere. " 2 We have been studying the cellular and biochemical

Aft2, a Novel Transcription Regulator, Is Required for Iron Metabolism, Oxidative Stress, Surface Adhesion and Hyphal Development in Candida albicans

PubMed Central

Xu, Ning; Cheng, Xinxin; Yu, Qilin; Qian, Kefan; Ding, Xiaohui; Liu, Ruming; Zhang, Biao; Xing, Laijun; Li, Mingchun

2013-01-01

Morphological transition and iron metabolism are closely relevant to Candida albicans pathogenicity and virulence. In our previous study, we demonstrated that C. albicans Aft2 plays an important role in ferric reductase activity and virulence. Here, we further explored the roles of C. albicans Aft2 in numerous cellular processes. We found that C. albicans Aft2 exhibited an important role in iron metabolism through bi-directional regulation effects on iron-regulon expression. Deletion of AFT2 reduced cellular iron accumulation under iron-deficient conditions. Furthermore, both reactive oxygen species (ROS) generation and superoxide dismutase (SOD) activity were remarkably increased in the aft2Δ/Δ mutant, which were thought to be responsible for the defective responses to oxidative stress. However, we found that over-expression of C. albicans AFT2 under the regulation of the strong PGK1 promoter could not effectively rescue Saccharomyces cerevisiae aft1Δ mutant defects in some cellular processes, such as cell-wall assembly, ion homeostasis and alkaline resistance, suggesting a possibility that C. albicans Aft2 weakened its functional role of regulating some cellular metabolism during the evolutionary process. Interestingly, deletion of AFT2 in C. albicans increased cell surface hydrophobicity, cell flocculation and the ability of adhesion to polystyrene surfaces. In addition, our results also revealed that C. albicans Aft2 played a dual role in regulating hypha-specific genes under solid and liquid hyphal inducing conditions. Deletion of AFT2 caused an impaired invasive growth in solid medium, but an increased filamentous aggregation and growth in liquid conditions. Moreover, iron deficiency and environmental cues induced nuclear import of Aft2, providing additional evidence for the roles of Aft2 in transcriptional regulation. PMID:23626810

Modulation of innate and adaptive cellular immunity relevant to HIV-1 vaccine design by seminal plasma.

PubMed

Selva, Kevin J; Kent, Stephen J; Parsons, Matthew S

2017-01-28

Mucosal exposure to HIV-1 infection generally occurs in the presence of semen. Immunomodulation by seminal plasma is well described in the reproductive biology literature. Little is known, however, about the impact of seminal plasma on innate and adaptive anti-HIV-1 cellular immunity. The study investigated the effects of seminal plasma on immune responses considered important for prophylactic HIV-1 vaccine development, namely innate and adaptive cellular immunity mediated by natural killer (NK) cells and T cells, respectively. The ability of seminal plasma to modulate direct, antibody-dependent and cytokine-stimulated NK cell activation was assessed utilizing intracellular cytokine staining. Direct and antibody-dependent cellular cytotoxicity was assessed using lactate dehydrogenase release assays. The effects of seminal plasma on T-cell activation upon stimulation with staphylococcus enterotoxin B or HIV-1 Gag peptides were assessed by intracellular cytokine staining. The impact of seminal plasma on redirected cytolysis mediated by T cells was measured using lactate dehydrogenase release assays. Both direct and antibody-dependent NK cell activation were dramatically impaired by the presence of either HIV-1-uninfected or HIV-1-infected seminal plasma in a dose-dependent manner. Additionally, seminal plasma suppressed both direct and antibody-dependent NK cell-mediated cytolysis, including anti-HIV-1 antibody-dependent cytolysis of gp120-pulsed CEM.NKr-CCR5 cells. Finally, seminal plasma attenuated both HIV-1 Gag-specific and staphylococcus enterotoxin B-induced CTL activation. Semen contains potent immunosuppressors of both NK cell and CD8 T-cell-mediated anti-HIV-1 immune responses. This could impede attempts to provide vaccine-induced immunity to HIV-1.

Cytotoxicity and Physiological Effects of Silver Nanoparticles on Marine Invertebrates.

PubMed

Magesky, Adriano; Pelletier, Émilien

2018-01-01

Silver nanoparticles (AgNPs) incorporation in commercial products is increasing due to their remarkable physical and chemical properties and their low cost on the market. Silver has been known for a long time to be highly toxic to bacterial communities, aquatic organisms, and particularly to marine biota. Strong chloro-complexes dominate Ag speciation in seawater and facilitate its persistence in dissolved form. It has a great impact on marine organisms because low concentration of silver can lead to strong bioaccumulation, partly because the neutral silver chloro complex (AgCl 0 ) is highly bioavailable. Owing to the fact that estuaries and coastal areas are considered as the ultimate fate for AgNPs, the study of their toxic effects on marine invertebrates can reveal some environmental risks related to nanosilver exposure. In an attempt to reach this goal, many invertebrate taxa including mollusks, crustaceans, echinoderms and polychaetes have been used as biological models. The main findings related to AgNP toxicity and marine invertebrates are summarized hereafter. Some cellular mechanisms involving nano-internalization (cellular uptake, distribution and elimination), DNA damaging, antioxidant cellular defenses and protein expression are discussed. Physiological effects on early stage development, silver metabolic speciation, immune response, tissue damaging, anti-oxidant effects and nano-depuration are also described. Finally, we paid attention to some recent interesting findings using sea urchin developmental stages and their cells as models for nanotoxicity investigation. Cellular and physiological processes characterizing sea urchin development revealed new and multiple toxicity mechanisms of both soluble and nano forms of silver.

Bioelectronic Sensors and Devices

NASA Astrophysics Data System (ADS)

Reed, Mark

Nanoscale electronic devices have recently enabled the ability to controllably probe biological systems, from the molecular to the cellular level, opening up new applications and understanding of biological function and response. This talk reviews some of the advances in the field, ranging from diagnostic and therapeutic applications, to cellular manipulation and response, to the emulation of biological response. In diagnostics, integrated nanodevice biosensors compatible with CMOS technology have achieved unprecedented sensitivity, enabling a wide range of label-free biochemical and macromolecule sensing applications down to femtomolar concentrations. These systems have demonstrated integrated assays of biomarkers at clinically important concentrations for both diagnostics and as a quantitative tool for drug design and discovery. Cellular level response can also be observed, including immune response function and dynamics. Finally, the field is beginning to create devices that emulate function, and the demonstration of a solid state artificial ion channel will be discussed.

Transforming growth factor-beta1 mediates cellular response to DNA damage in situ

NASA Technical Reports Server (NTRS)

Ewan, Kenneth B.; Henshall-Powell, Rhonda L.; Ravani, Shraddha A.; Pajares, Maria Jose; Arteaga, Carlos; Warters, Ray; Akhurst, Rosemary J.; Barcellos-Hoff, Mary Helen

2002-01-01

Transforming growth factor (TGF)-beta1 is rapidly activated after ionizing radiation, but its specific role in cellular responses to DNA damage is not known. Here we use Tgfbeta1 knockout mice to show that radiation-induced apoptotic response is TGF-beta1 dependent in the mammary epithelium, and that both apoptosis and inhibition of proliferation in response to DNA damage decrease as a function of TGF-beta1 gene dose in embryonic epithelial tissues. Because apoptosis in these tissues has been shown previously to be p53 dependent, we then examined p53 protein activation. TGF-beta1 depletion, by either gene knockout or by using TGF-beta neutralizing antibodies, resulted in decreased p53 Ser-18 phosphorylation in irradiated mammary gland. These data indicate that TGF-beta1 is essential for rapid p53-mediated cellular responses that mediate cell fate decisions in situ.

Curcumin enhances recovery of pancreatic islets from cellular stress induced inflammation and apoptosis in diabetic rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rashid, Kahkashan; Sil, Parames C., E-mail: parames@jcbose.ac.in

The phytochemical, curcumin, has been reported to play many beneficial roles. However, under diabetic conditions, the detail mechanism of its beneficial action in the glucose homeostasis regulatory organ, pancreas, is poorly understood. The present study has been designed and carried out to explore the role of curcumin in the pancreatic tissue of STZ induced and cellular stress mediated diabetes in eight weeks old male Wistar rats. Diabetes was induced with a single intraperitoneal dose of STZ (65 mg/kg body weight). Post to diabetes induction, animals were treated with curcumin at a dose of 100 mg/kg body weight for eight weeks.more » Underlying molecular and cellular mechanism was determined using various biochemical assays, DNA fragmentation, FACS, histology, immunoblotting and ELISA. Treatment with curcumin reduced blood glucose level, increased plasma insulin and mitigated oxidative stress related markers. In vivo and in vitro experimental results revealed increased levels of proinflammatory cytokines (TNF-α, IL1-β and IFN-γ), reduced level of cellular defense proteins (Nrf-2 and HO-1) and glucose transporter (GLUT-2) along with enhanced levels of signaling molecules of ER stress dependent and independent apoptosis (cleaved Caspase-12/9/8/3) in STZ administered group. Treatment with curcumin ameliorated all the adverse changes and helps the organ back to its normal physiology. Results suggest that curcumin protects pancreatic beta-cells by attenuating inflammatory responses, and inhibiting ER/mitochondrial dependent and independent pathways of apoptosis and crosstalk between them. This uniqueness and absence of any detectable adverse effect proposes the possibility of using this molecule as an effective protector in the cellular stress mediated diabetes mellitus. - Highlights: • STZ induced cellular stress plays a vital role in pancreatic dysfunction. • Cellular stress causes inflammation, pancreatic islet cell death and diabetes. • Deregulation of Nrf-2 mediated antioxidant defense machinery takes place. • Islet cells undergo apoptosis (via ER/mitochondrial dependent/independent pathways). • Curcumin protects pancreatic β-cells from the adverse effects of cellular stress.« less

A core viral protein binds host nucleosomes to sequester immune danger signals

PubMed Central

Avgousti, Daphne C.; Herrmann, Christin; Kulej, Katarzyna; Pancholi, Neha J.; Sekulic, Nikolina; Petrescu, Joana; Molden, Rosalynn C.; Blumenthal, Daniel; Paris, Andrew J.; Reyes, Emigdio D.; Ostapchuk, Philomena; Hearing, Patrick; Seeholzer, Steven H.; Worthen, G. Scott; Black, Ben E.; Garcia, Benjamin A.; Weitzman, Matthew D.

2016-01-01

Viral proteins mimic host protein structure and function to redirect cellular processes and subvert innate defenses1. Small basic proteins compact and regulate both viral and cellular DNA genomes. Nucleosomes are the repeating units of cellular chromatin and play an important role in innate immune responses2. Viral encoded core basic proteins compact viral genomes but their impact on host chromatin structure and function remains unexplored. Adenoviruses encode a highly basic protein called protein VII that resembles cellular histones3. Although protein VII binds viral DNA and is incorporated with viral genomes into virus particles4,5, it is unknown whether protein VII impacts cellular chromatin. Our observation that protein VII alters cellular chromatin led us to hypothesize that this impacts antiviral responses during adenovirus infection. We found that protein VII forms complexes with nucleosomes and limits DNA accessibility. We identified post-translational modifications on protein VII that are responsible for chromatin localization. Furthermore, proteomic analysis demonstrated that protein VII is sufficient to alter protein composition of host chromatin. We found that protein VII is necessary and sufficient for retention in chromatin of members of the high-mobility group protein B family (HMGB1, HMGB2, and HMGB3). HMGB1 is actively released in response to inflammatory stimuli and functions as a danger signal to activate immune responses6,7. We showed that protein VII can directly bind HMGB1 in vitro and further demonstrated that protein VII expression in mouse lungs is sufficient to decrease inflammation-induced HMGB1 content and neutrophil recruitment in the bronchoalveolar lavage fluid. Together our in vitro and in vivo results show that protein VII sequesters HMGB1 and can prevent its release. This study uncovers a viral strategy in which nucleosome binding is exploited to control extracellular immune signaling. PMID:27362237

Real-time Molecular Study of Bystander Effects of Low dose Low LET radiation Using Living Cell Imaging and Nanoparticale Optics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Natarajan, Mohan; Xu, Nancy R; Mohan, Sumathy

2013-06-03

In this study two novel approaches are proposed to investigate precisely the low dose low LET radiation damage and its effect on bystander cells in real time. First, a flow shear model system, which would provide us a near in vivo situation where endothelial cells in the presence of extra cellular matrix experiencing continuous flow shear stress, will be used. Endothelial cells on matri-gel (simulated extra cellular matrix) will be subjected to physiological flow shear (that occurs in normal blood vessels). Second, a unique tool (Single nano particle/single live cell/single molecule microscopy and spectroscopy; Figure A) will be used tomore » track the molecular trafficking by single live cell imaging. Single molecule chemical microscopy allows one to single out and study rare events that otherwise might be lost in assembled average measurement, and monitor many target single molecules simultaneously in real-time. Multi color single novel metal nanoparticle probes allow one to prepare multicolor probes (Figure B) to monitor many single components (events) simultaneously and perform multi-complex analysis in real-time. These nano-particles resist to photo bleaching and hence serve as probes for unlimited timeframe of analysis. Single live cell microscopy allows one to image many single cells simultaneously in real-time. With the combination of these unique tools, we will be able to study under near-physiological conditions the cellular and sub-cellular responses (even subtle changes at one molecule level) to low and very low doses of low LET radiation in real time (milli-second or nano-second) at sub-10 nanometer spatial resolution. This would allow us to precisely identify, at least in part, the molecular mediators that are responsible of radiation damage in the irradiated cells and the mediators that are responsible for initiating the signaling in the neighboring cells. Endothelial cells subjected to flow shear (2 dynes/cm2 or 16 dynes/cm2) and exposed to 0.1, 1 and 10 cGy on coverslips will be examined for (a) low LET radiation-induced alterations of cellular function and its physiological relevance in real time; and (b) radiation damage triggered bystander effect on the neighboring unirradiated cells. First, to determine the low LET radiation induced alteration of cellular function we will examine: (i) the real time transformation of single membrane transporters in single living cells; (ii) the pump efficiency of membrane efflux pump of live cells in real time at the molecular level; (iii) the kinetics of single-ligand receptor interaction on single live cell surface (Figure C); and (iv) alteration in chromosome replication in living cell. Second, to study the radiation triggered bystander responses, we will examine one of the key signaling pathway i.e. TNF- alpha/NF-kappa B mediated signaling. TNF-alpha specific nano particle sensors (green) will be developed to detect the releasing dynamics, transport mechanisms and ligand-receptor binding on live cell surface in real time. A second sensor (blue) will be developed to simultaneously monitor the track of NF-kB inside the cell. The proposed nano-particle optics approach would complement our DOE funded study on biochemical mechanisms of TNF-alpha- NF-kappa B-mediated bystander effect.« less

Role of cellular communication in the pathways of radiation-induced biological damage

NASA Astrophysics Data System (ADS)

Ballarini, Francesca; Facoetti, Angelica; Mariotti, Luca; Nano, Rosanna; Ottolenghi, Andrea

During the last decade, a large number of experimental studies on the so-called "non-targeted effects", in particular bystander effects, outlined that cellular communication plays a signifi- cant role in the pathways leading to radiation-induced biological damage. This might imply a paradigm shift in (low-dose) radiobiology, according to which one has to consider the response of groups of cells behaving like a population rather than single cells behaving as individuals. Furthermore, bystander effects, which are observed both for lethal endpoints (e.g. clonogenic inactivation and apoptosis) and for non-lethal ones (e.g. mutations and neoplastic transformation), tend to show non-linear dose responses characterized by a sharp increase followed by a plateau. This might have significant consequences in terms of low-dose risk, which is generally calculated on the basis of the "Linear No Threshold" hypothesis. Although it is known that two types of cellular communication (i.e. via gap junctions and/or molecular messengers diffusing in the extra-cellular environment, such as cytokines) play a major role, it is of utmost importance to better understand the underlying mechanisms, and how such mechanisms can be modulated by ionizing radiation. Though the "final" goal is to elucidate the in vivo scenario, in the meanwhile also in vitro studies can provide useful insights. In the present paper we will discuss key issues on the mechanisms underlying non-targeted effects and, more generally, cell communication, with focus on candidate molecular signals. Theoretical models and simulation codes can be of help in elucidating such mechanisms. In this framework, we will present a model and Monte Carlo code, under development at the University of Pavia, simulating the release, diffusion and internalization of candidate signals (typically cytokines) travelling in the extra-cellular environment, both by unirradiated (i.e., control) cells and by irradiated cells. The focus will be on the role of critical parameters such as the cell number and density, the amount of culture medium etc. Comparisons with ad hoc experimental data obtained in our laboratory will be presented, and possible implications in terms of low-dose risk assessment will be discussed. Work supported by the European Community (projects "RISC-RAD" and "NOTE") and the Italian Space Agency (project "MoMa/COUNT)

Cellular Imaging With MRI.

PubMed

Makela, Ashley V; Murrell, Donna H; Parkins, Katie M; Kara, Jenna; Gaudet, Jeffrey M; Foster, Paula J

2016-10-01

Cellular magnetic resonance imaging (MRI) is an evolving field of imaging with strong translational and research potential. The ability to detect, track, and quantify cells in vivo and over time allows for studying cellular events related to disease processes and may be used as a biomarker for decisions about treatments and for monitoring responses to treatments. In this review, we discuss methods for labeling cells, various applications for cellular MRI, the existing limitations, strategies to address these shortcomings, and clinical cellular MRI.

Ceftiofur hydrochloride affects the humoral and cellular immune response in pigs after vaccination against swine influenza and pseudorabies.

PubMed

Pomorska-Mól, Małgorzata; Czyżewska-Dors, Ewelina; Kwit, Krzysztof; Wierzchosławski, Karol; Pejsak, Zygmunt

2015-10-22

Cephalosporins are a class of antibiotics that are active against many Gram-positive and some Gram-negative bacteria. Beyond their antibacterial activity, they are reported to have various immunomodulatory properties. It has been shown that they reduce the secretion of cytokines as well as influence the humoral and cellular immune response. In the field conditions antibiotics are frequently administered at the same time as vaccines in pigs and, in the view of their potential immunomodulatory properties, it is important to examine their effect on the development and persistence of the post-vaccinal immune response. Ceftiofur is a very popular veterinary medicine third-generation cephalosporin with a broad spectrum of activity. It has been shown that it can inhibit cytokines secretion and in this way can potentially affect host immune response. The influence of ceftiofur on the immune response has not yet been investigated in pigs. In the present study we evaluated the influence of therapeutic doses of ceftiofur hydrochloride on the post-vaccinal immune response after vaccination with two model vaccines (live and inactivated). Seventy pigs were divided into five groups: control, unvaccinated (C), control vaccinated against swine influenza (SI-V), control vaccinated against pseudorabies (PR-V), vaccinated against SI during ceftiofur administration (SI-CEF) and vaccinated against PR during ceftiofur administration (PR-CEF). Pigs from SICEF and PR-CEF groups received therapeutic dose of ceftiofur for five days. Pigs from SI-CEF, PR-CEF, SIV and PR-V groups were vaccinated against SI and PR. Antibodies to PRV were determined with the use of blocking ELISA tests (IDEXX Laboratories, USA). Humoral responses to SIV were assessed based on haemagglutination inhibition assay. T-cell response was analyzed with the use of proliferation test. The concentrations of IFN- γ and IL-4 in culture supernatant were determined with the use of ELISA kits Invitrogen Corporation, USA). The significant delay in the development of humoral response against pseudorabies virus (PRV) as well as a significant suppression of production of antibodies against swine influenza virus (SIV) was found in pigs receiving ceftiofur hydrochloride at the time of vaccination. The cellular immune response against PRV was also significantly affected by ceftiofur. In contrast, there were no significant differences between vaccinated groups with regard to the T-cell response against SIV. From day 28 of study to day 70, the concentration of INF-γ in culture supernatants were significantly lower in group treated with ceftiofur after restimulation with PRV. While, no significant differences were observed after restimulation of PBMC with H3N2 SIV. The effect of an antibiotic therapy with ceftiofur hydrochloride on the humoral and cellular post-vaccinal immune responses in pigs was investigated. Ceftiofur hydrochloride was given in therapeutic doses. The results of the present study indicate that both, humoral and cell-mediated post-vaccinal immune responses can be modulated by treatment with ceftiofur hydrochloride. The results of our study point out that caution should be taken when administered this antibiotic during vaccination of pigs.

Povidone-Iodine Has a Profound Effect on In Vitro Osteoblast Proliferation and Metabolic Function and Inhibits Their Ability to Mineralize and Form Bone.

PubMed

Newton Ede, Matthew P; Philp, Ashleigh M; Philp, Andrew; Richardson, Stephen M; Mohammad, Saeed; Jones, Simon W

2016-05-01

A study examining the clinical protocol of scoliosis wound irrigation, demonstrating povidone-iodine's (PVI) effect on human osteoblast cells. Primary and immortal cell line osteoblasts were treated with 0.35% PVI for 3 minutes, and analyzed for proliferation rate, oxidative capacity, and mineralization. To model spinal wound irrigation with dilute PVI in vitro, in order to investigate the effect of PVI on osteoblast proliferation, metabolism, and bone mineralization. Previously PVI irrigation has been proposed as a safe and effective practice to avoid bacterial growth after spinal surgery. However, recent evidence in multiple cell types suggests that PVI has a deleterious effect on cellular viability and cellular function. Primary and immortal human osteoblast cells were exposed to either phosphate buffered saline control or with 0.35% PVI for 3 minutes. Cellular proliferation was measured over the duration of 7 days by MTS assay. Oxygen consumption rate, extracellular acidification rate, and proton production rate were analyzed using a Seahorse XF24 Bioanalyzer. Protein expression of the electron transport chain subunits CII-SDHB, CIII-UQRCR2, and CV-ATP5A was measured via Western blotting. Mineralized bone nodules were stained with alizarin red. Expressed as a percentage of normal osteoblast proliferation, osteoblasts exposed to 0.35% PVI exhibited a significant 24% decrease in proliferation after 24 hours. This was a sustained response, resulting in a 72% decline in cellular proliferation at 1 week. There was a significant reduction in oxygen consumption rate, extracellular acidification rate, and proton production rate (P < 0.05), in osteoblasts that had been exposed to 0.35% PVI for 3 minutes, coupled with a marked reduction in the protein expression of CII-SDHB. Osteoblasts exposed to 0.35% PVI exhibited reduced bone nodule mineralization compared to control phosphate buffered saline exposed osteoblasts (P < 0.01). PVI has a rapid and detrimental effect on human osteoblast cellular proliferation, metabolic function, and bone nodule mineralization. NA.

Biological Clues to Potent DNA-Damaging Activities in Food and Flavoring

PubMed Central

Hossain, M. Zulfiquer; Gilbert, Samuel F.; Patel, Kalpesh; Ghosh, Soma; Bhunia, Anil K.; Kern, Scott E.

2013-01-01

Population differences in age-related diseases and cancer could stem from differences in diet. To characterize DNA strand-breaking activities in selected foods/beverages, flavorings, and some of their constituent chemicals, we used p53R cells, a cellular assay sensitive to such breaks. Substances testing positive included reference chemicals: quinacrine (peak response, 51X) and etoposide (33X); flavonoids: EGCG (19X), curcumin (12X), apigenin (9X), and quercetin (7X); beverages: chamomile (11X), green (21X), and black tea (26X) and coffee (3 to 29X); and liquid smoke (4 to 28X). Damage occurred at dietary concentrations: etoposide near 5 μg/ml produced responses similar to a 1:1000 dilution of liquid smoke, a 1:20 dilution of coffee, and a 1:5 dilution of tea. Pyrogallol-related chemicals and tannins are present in dietary sources and individually produced strong activity: pyrogallol (30X), 3-methoxycatechol (25X), gallic acid (21X), and 1,2,4-benzenetriol (21X). From structure-activity relationships, high activities depended on specific orientations of hydroxyls on the benzene ring. Responses accompanied cellular signals characteristic of DNA breaks such as H2AX phosphorylation. Breaks were also directly detected by comet assay. Cellular toxicological effects of foods and flavorings could guide epidemiologic and experimental studies of potential disease risks from DNA strand-breaking chemicals in diets. PMID:23402862

Selective expression of inhibitory Fcgamma receptor by metastatic melanoma impairs tumor susceptibility to IgG-dependent cellular response.

PubMed

Cassard, Lydie; Cohen-Solal, Joel F G; Fournier, Emilie M; Camilleri-Broët, Sophie; Spatz, Alain; Chouaïb, Salem; Badoual, Cécile; Varin, Audrey; Fisson, Sylvain; Duvillard, Pierre; Boix, Charlotte; Loncar, Shannon M; Sastre-Garau, Xavier; Houghton, Alan N; Avril, Marie-Françoise; Gresser, Ion; Fridman, Wolf H; Sautès-Fridman, Catherine

2008-12-15

During melanoma progression, patients develop anti-tumor immunity including the production of anti-tumor antibodies. Although the strategies developed by malignant cells to escape anti-tumor cellular immunity have been extensively investigated, little is known about tumor resistance to humoral immunity. The main effect of IgG antibodies is to activate the immune response by binding to host Fc gamma receptors (FcgammaR) expressed by immune cells. We previously reported in a limited study that some human metastatic melanoma cells ectopically express the FcgammaRIIB1, an inhibitory isoform of FcgammaR. By analyzing a large panel of different types of human primary and metastatic solid tumors, we report herein that expression of FcgammaRIIB is restricted to melanoma and is acquired during tumor progression. We show that FcgammaRIIB expression prevents the lysis of human metastatic melanoma cells by NK cell-mediated antibody-dependent cellular cytotoxicity (ADCC) in vitro, independently of the intracytoplasmic region of FcgammaRIIB. Using experimental mouse models, we demonstrate that expression of FcgammaRIIB protects B16F0 melanoma tumors from the ADCC induced by monoclonal and polyclonal anti-tumor IgG in vivo. Thus, our results identify FcgammaRIIB as a marker of human metastatic melanoma that impairs the tumor susceptibility to FcgammaR-dependent innate effector responses. (c) 2008 Wiley-Liss, Inc.

Onchocerciasis modulates the immune response to mycobacterial antigens

PubMed Central

Stewart, G R; Boussinesq, M; Coulson, T; Elson, L; Nutman, T; Bradley, J E

1999-01-01

Chronic helminth infection induces a type-2 cellular immune response. In contrast to this, mycobacterial infections commonly induce a type-1 immune response which is considered protective. Type-2 responses and diminished type-1 responses to mycobacteria have been previously correlated with active infection states such as pulmonary tuberculosis and lepromatous leprosy. The present study examines the immune responses of children exposed to both the helminth parasite Onchocerca volvulus and the mycobacterial infections, Mycobacterium tuberculosis and M. leprae. Proliferation of peripheral blood mononuclear cells (PBMC) and production of IL-4 in response to both helminth and mycobacterial antigen (PPD) decreased dramatically with increasing microfilarial (MF) density. Although interferon-gamma (IFN-γ) production strongly correlated with cellular proliferation, it was surprisingly not related to MF density for either antigen. IL-4 production in response to helminth antigen and PPD increased with ascending children's age. IFN-γ and cellular proliferation to PPD were not related to age, but in response to helminth antigen were significantly higher in children of age 9–12 years than children of either the younger age group (5–8 years) or the older group (13–16 years). Thus, there was a MF density-related down-regulation of cellular responsiveness and age-related skewing toward type 2 which was paralleled in response to both the helminth antigen and PPD. This parasite-induced immunomodulation of the response to mycobacteria correlates with a previous report of doubled incidence of lepromatous leprosy in onchocerciasis hyperendemic regions. Moreover, this demonstration that helminth infection in humans can modulate the immune response to a concurrent infection or immunological challenge is of critical importance to future vaccination strategies. PMID:10469056

A cellular and molecular basis for the selective desmopressin-induced ACTH release in Cushing disease patients: key role of AVPR1b receptor and potential therapeutic implications.

PubMed

Luque, R M; Ibáñez-Costa, A; López-Sánchez, L M; Jiménez-Reina, L; Venegas-Moreno, E; Gálvez, M A; Villa-Osaba, A; Madrazo-Atutxa, A M; Japón, M A; de la Riva, A; Cano, D A; Benito-López, P; Soto-Moreno, A; Gahete, M D; Leal-Cerro, A; Castaño, J P

2013-10-01

Desmopressin is a synthetic agonist of vasopressin receptors (AVPRs). The desmopressin stimulation test is used in the diagnosis and postsurgery prognosis of Cushing disease (CD). However, the cellular and molecular mechanisms underlying the desmopressin-induced ACTH increase in patients with CD are poorly understood. The objectives of this study were to determine, for the first time, whether desmopressin acts directly and exclusively on pituitary corticotropinoma cells to stimulate ACTH expression/release and to elucidate the cellular and molecular mechanisms involved in desmopressin-induced ACTH increase in CD. A total of 8 normal pituitaries (NPs), 23 corticotropinomas, 14 nonfunctioning pituitary adenomas, 17 somatotropinomas, and 3 prolactinomas were analyzed for AVPR expression by quantitative real-time RT-PCR. Primary cultures derived from corticotropinomas, nonfunctioning pituitary adenomas, somatotropinomas, prolactinomas, and NPs were treated with desmopressin, and ACTH secretion/expression, [Ca(2+)]i kinetics, and AVPR expression and/or proliferative response were evaluated. The relationship between AVPR expression and plasma adrenocorticotropin/cortisol levels obtained from desmopressin tests was assessed. Desmopressin affects all functional parameters evaluated in corticotropinoma cells but not in NPs or other pituitary adenomas cells. These effects might be due to the dramatic elevation of AVPR1b expression levels found in corticotropinomas. In line with this notion, the use of an AVPR1b antagonist completely blocked desmopressin stimulatory effects. Remarkably, only AVPR1b expression was positively correlated with elevated plasma adrenocorticotropin levels in corticotropinomas. The present results provide a cellular and molecular basis to support the desmopressin stimulation test as a reliable, specific test for the diagnosis and postsurgery prognosis of CD. Furthermore, our data indicate that AVPR1b is responsible for the direct/exclusive desmopressin stimulatory pituitary effects observed in CD, thus opening the possibility of exploring AVPR1b antagonists as potential therapeutic tools for CD treatment.

Cellular immune responses against CT7 (MAGE-C1) and humoral responses against other cancer-testis antigens in multiple myeloma patients

PubMed Central

Lendvai, Nikoletta; Gnjatic, Sacha; Ritter, Erika; Mangone, Michael; Austin, Wayne; Reyner, Karina; Jayabalan, David; Niesvizky, Ruben; Jagannath, Sundar; Bhardwaj, Nina; Chen-Kiang, Selina; Old, Lloyd J.

2010-01-01

The type I melanoma antigen gene (MAGE) proteins CT7 (MAGE-C1) and MAGE-A3 are commonly expressed in multiple myeloma (MM), and their expression correlates with increased plasma cell proliferation and poor clinical outcome. They belong to the cancer-testis antigen (CTAg) group of tumor-associated proteins, some of which elicit spontaneous immune responses in cancer patients. CT7 and MAGE-A3 are promising antigenic targets for therapeutic tumor vaccines in myeloma; therefore, it is critical to determine if they are immunogenic in MM patients. We analyzed cellular and humoral immune responses against CTAgs in patients with plasma cell dyscrasias: MM, monoclonal gammopathy of undetermined significance (MGUS), and Waldenström's macroglobulinemia (WM). Bone marrow lymphocytes from two of four untreated MM patients exhibited CT7-specific cellular immune responses as measured by an autologous cellular immunity assay, the first such immune response to CT7 to be reported in cancer patients. Sera from 24 patients were screened by ELISA for humoral immune responses to CTAgs. Two patients with MM demonstrated positive titers, one for MAGE-A1 and the other for SSX1. These data demonstrate that CTAgs, particularly CT7, are immunogenic in MM patients and merit further exploration as targets of immunological therapy in MM. PMID:20108890

Cellular immune responses against CT7 (MAGE-C1) and humoral responses against other cancer-testis antigens in multiple myeloma patients.

PubMed

Lendvai, Nikoletta; Gnjatic, Sacha; Ritter, Erika; Mangone, Michael; Austin, Wayne; Reyner, Karina; Jayabalan, David; Niesvizky, Ruben; Jagannath, Sundar; Bhardwaj, Nina; Chen-Kiang, Selina; Old, Lloyd J; Cho, Hearn Jay

2010-01-29

The type I melanoma antigen gene (MAGE) proteins CT7 (MAGE-C1) and MAGE-A3 are commonly expressed in multiple myeloma (MM), and their expression correlates with increased plasma cell proliferation and poor clinical outcome. They belong to the cancer-testis antigen (CTAg) group of tumor-associated proteins, some of which elicit spontaneous immune responses in cancer patients. CT7 and MAGE-A3 are promising antigenic targets for therapeutic tumor vaccines in myeloma; therefore, it is critical to determine if they are immunogenic in MM patients. We analyzed cellular and humoral immune responses against CTAgs in patients with plasma cell dyscrasias: MM, monoclonal gammopathy of undetermined significance (MGUS), and Waldenström's macroglobulinemia (WM). Bone marrow lymphocytes from two of four untreated MM patients exhibited CT7-specific cellular immune responses as measured by an autologous cellular immunity assay, the first such immune response to CT7 to be reported in cancer patients. Sera from 24 patients were screened by ELISA for humoral immune responses to CTAgs. Two patients with MM demonstrated positive titers, one for MAGE-A1 and the other for SSX1. These data demonstrate that CTAgs, particularly CT7, are immunogenic in MM patients and merit further exploration as targets of immunological therapy in MM.

The expanding universe of hypoxia.

PubMed

Zhang, Huafeng; Semenza, Gregg L

2008-07-01

Reduced oxygen availability (hypoxia) is sensed and transduced into changes in the activity or expression of cellular macromolecules. These responses impact on virtually all areas of biology and medicine. In this meeting report, we summarize major developments in the field that were presented at the 2008 Keystone Symposium on Cellular, Physiological, and Pathogenic Responses to Hypoxia.

Thiol peroxidases mediate specific genome-wide regulation of gene expression in response to hydrogen peroxide

PubMed Central

Fomenko, Dmitri E.; Koc, Ahmet; Agisheva, Natalia; Jacobsen, Michael; Kaya, Alaattin; Malinouski, Mikalai; Rutherford, Julian C.; Siu, Kam-Leung; Jin, Dong-Yan; Winge, Dennis R.; Gladyshev, Vadim N.

2011-01-01

Hydrogen peroxide is thought to regulate cellular processes by direct oxidation of numerous cellular proteins, whereas antioxidants, most notably thiol peroxidases, are thought to reduce peroxides and inhibit H2O2 response. However, thiol peroxidases have also been implicated in activation of transcription factors and signaling. It remains unclear if these enzymes stimulate or inhibit redox regulation and whether this regulation is widespread or limited to a few cellular components. Herein, we found that Saccharomyces cerevisiae cells lacking all eight thiol peroxidases were viable and withstood redox stresses. They transcriptionally responded to various redox treatments, but were unable to activate and repress gene expression in response to H2O2. Further studies involving redox transcription factors suggested that thiol peroxidases are major regulators of global gene expression in response to H2O2. The data suggest that thiol peroxidases sense and transfer oxidative signals to the signaling proteins and regulate transcription, whereas a direct interaction between H2O2 and other cellular proteins plays a secondary role. PMID:21282621

Endoplasmic reticulum stress-induced apoptosis accompanies enhanced expression of multiple inositol polyphosphate phosphatase 1 (Minpp1): a possible role for Minpp1 in cellular stress response.

PubMed

Kilaparty, Surya P; Agarwal, Rakhee; Singh, Pooja; Kannan, Krishnaswamy; Ali, Nawab

2016-07-01

Inositol polyphosphates represent a group of differentially phosphorylated inositol metabolites, many of which are implicated to regulate diverse cellular processes such as calcium mobilization, vesicular trafficking, differentiation, apoptosis, etc. The metabolic network of these compounds is complex and tightly regulated by various kinases and phosphatases present predominantly in the cytosol. Multiple inositol polyphosphate phosphatase 1 (Minpp1) is the only known endoplasmic reticulum (ER) luminal enzyme that hydrolyzes various inositol polyphosphates in vitro as well as in vivo conditions. However, access of the Minpp1 to cytosolic substrates has not yet been demonstrated clearly and hence its physiological function. In this study, we examined a potential role for Minpp1 in ER stress-induced apoptosis. We generated a custom antibody and characterized its specificity to study the expression of Minpp1 protein in multiple mammalian cells under experimentally induced cellular stress conditions. Our results demonstrate a significant increase in the expression of Minpp1 in response to a variety of cellular stress conditions. The protein expression was corroborated with the expression of its mRNA and enzymatic activity. Further, in an attempt to link the role of Minpp1 to apoptotic stress, we studied the effect of Minpp1 expression on apoptosis following silencing of the Minpp1 gene by its specific siRNA. Our results suggest an attenuation of apoptotic parameters following knockdown of Minpp1. Thus, in addition to its known role in inositol polyphosphate metabolism, we have identified a novel role for Minpp1 as a stress-responsive protein. In summary, our results provide, for the first time, a probable link between ER stress-induced apoptosis and Minpp1 expression.

redox Signaling by 8-nitro-cyclic guanosine monophosphate: nitric oxide- and reactive oxygen species-derived electrophilic messenger.

PubMed

Fujii, Shigemoto; Akaike, Takaaki

2013-10-10

Emerging evidence has revealed that nitric oxide (NO)- and reactive oxygen species (ROS)-derived electrophiles formed in cells mediate signal transduction for responses to oxidative stress. The cyclic nucleotide with a nitrated guanine moiety-8-nitroguanosine 3',5'-cyclic monophosphate (8-nitro-cGMP)-first identified in 2007 as a second messenger for NO and ROS-has certain unique properties that its parental cGMP lacks. For example, it can react with particular protein Cys thiols because of its electrophilicity and can cause unique post-translational modifications of redox-sensor proteins such as Keap1 and H-Ras. Site-specific S-guanylation of Keap1 at Cys434 induced NO- and ROS-mediated adaptive responses to oxidative stress. H-Ras Cys184 S-guanylation was recently found to be involved in activation of mitogen-activated protein kinase cascades as manifested by cellular senescence and heart failure in mouse cardiac hypertrophy models. The latest finding related to the concept of electrophile-based redox signaling is a potent regulatory function of endogenously produced hydrogen sulfide for redox signaling via 8-nitro-cGMP. Electrophile modification of 8-nitro-cGMP, as a second messenger for NO and ROS, by hydrogen sulfide (i.e., electrophile sulfhydration) can most likely effect physiological regulation of cellular redox signaling. Continued investigation of the precise function of cellular hydrogen sulfide that may control electrophile-dependent redox cellular signaling, most typically via 8-nitro-cGMP formation, may provide novel insights into the molecular mechanisms of oxidative stress responses, oxidative stress-related pathology and disease control, and development of therapeutics for various diseases.

Investigating membrane nanoporation induced by bipolar pulsed electric fields via second harmonic generation

NASA Astrophysics Data System (ADS)

Moen, E. K.; Ibey, B. L.; Beier, H. T.; Armani, A. M.

2016-09-01

Electric pulses have become an effective tool for transporting cargo (DNA, drugs, etc.) across cell membranes. This enhanced transport is believed to occur through temporary pores formed in the plasma membrane. Traditionally, millisecond duration, monopolar (MP) pulses are used for electroporation, but bipolar (BP) pulses have proven equally effective as MP pulses with the added advantage of less cytotoxicity. With the goal of further reducing cytotoxic effects and inducing non-thermal, intra-cellular effects, researchers began investigating reduced pulse durations, pushing into the nanosecond regime. Cells exposed to these MP, nanosecond pulsed electric fields (nsPEFs) have shown increased repairable membrane permeability and selective channel activation. However, attempts to improve this further by moving to the BP pulse regime has proven unsuccessful. In the present work, we use second harmonic generation imaging to explore the structural effects of bipolar nsPEFs on the plasma membrane. By varying the temporal spacing between the pulse phases over several orders of magnitude and comparing the response to a single MP case, we systematically examine the disparity in cellular response. Our circuit-based model predicts that, as the temporal spacing increases several orders of magnitude, nanoporation increases and eventually exceeds the MP case. On the whole, our experimental data agree with this assertion; however, a detailed analysis of the data sets demonstrates that biological processes may play a larger role in the observed response than previously thought, dominating the effect for temporal spacing up to 5 μs. These findings could ultimately lead to understanding the biophysical mechanism underlying all electroporation.

Hypoxia decreases creatine uptake in cardiomyocytes, while creatine supplementation enhances HIF activation.

PubMed

Santacruz, Lucia; Arciniegas, Antonio Jose Luis; Darrabie, Marcus; Mantilla, Jose G; Baron, Rebecca M; Bowles, Dawn E; Mishra, Rajashree; Jacobs, Danny O

2017-08-01

Creatine (Cr), phosphocreatine (PCr), and creatine kinases (CK) comprise an energy shuttle linking ATP production in mitochondria with cellular consumption sites. Myocytes cannot synthesize Cr: these cells depend on uptake across the cell membrane by a specialized creatine transporter (CrT) to maintain intracellular Cr levels. Hypoxia interferes with energy metabolism, including the activity of the creatine energy shuttle, and therefore affects intracellular ATP and PCr levels. Here, we report that exposing cultured cardiomyocytes to low oxygen levels rapidly diminishes Cr transport by decreasing V max and K m Pharmacological activation of AMP-activated kinase (AMPK) abrogated the reduction in Cr transport caused by hypoxia. Cr supplementation increases ATP and PCr content in cardiomyocytes subjected to hypoxia, while also significantly augmenting the cellular adaptive response to hypoxia mediated by HIF-1 activation. Our results indicate that: (1) hypoxia reduces Cr transport in cardiomyocytes in culture, (2) the cytoprotective effects of Cr supplementation are related to enhanced adaptive physiological responses to hypoxia mediated by HIF-1, and (3) Cr supplementation increases the cellular ATP and PCr content in RNCMs exposed to hypoxia. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

Disruptive chemicals, senescence and immortality

PubMed Central

Carnero, Amancio; Blanco-Aparicio, Carmen; Kondoh, Hiroshi; Lleonart, Matilde E.; Martinez-Leal, Juan Fernando; Mondello, Chiara; Ivana Scovassi, A.; Bisson, William H.; Amedei, Amedeo; Roy, Rabindra; Woodrick, Jordan; Colacci, Annamaria; Vaccari, Monica; Raju, Jayadev; Al-Mulla, Fahd; Al-Temaimi, Rabeah; Salem, Hosni K.; Memeo, Lorenzo; Forte, Stefano; Singh, Neetu; Hamid, Roslida A.; Ryan, Elizabeth P.; Brown, Dustin G.; Wise, John Pierce; Wise, Sandra S.; Yasaei, Hemad

2015-01-01

Carcinogenesis is thought to be a multistep process, with clonal evolution playing a central role in the process. Clonal evolution involves the repeated ‘selection and succession’ of rare variant cells that acquire a growth advantage over the remaining cell population through the acquisition of ‘driver mutations’ enabling a selective advantage in a particular micro-environment. Clonal selection is the driving force behind tumorigenesis and possesses three basic requirements: (i) effective competitive proliferation of the variant clone when compared with its neighboring cells, (ii) acquisition of an indefinite capacity for self-renewal, and (iii) establishment of sufficiently high levels of genetic and epigenetic variability to permit the emergence of rare variants. However, several questions regarding the process of clonal evolution remain. Which cellular processes initiate carcinogenesis in the first place? To what extent are environmental carcinogens responsible for the initiation of clonal evolution? What are the roles of genotoxic and non-genotoxic carcinogens in carcinogenesis? What are the underlying mechanisms responsible for chemical carcinogen-induced cellular immortality? Here, we explore the possible mechanisms of cellular immortalization, the contribution of immortalization to tumorigenesis and the mechanisms by which chemical carcinogens may contribute to these processes. PMID:26106138

Mitochondrial peptides modulate mitochondrial function during cellular senescence.

PubMed

Kim, Su-Jeong; Mehta, Hemal H; Wan, Junxiang; Kuehnemann, Chisaka; Chen, Jingcheng; Hu, Ji-Fan; Hoffman, Andrew R; Cohen, Pinchas

2018-06-10

Cellular senescence is a complex cell fate response that is thought to underlie several age-related pathologies. Despite a loss of proliferative potential, senescent cells are metabolically active and produce energy-consuming effectors, including senescence-associated secretory phenotypes (SASPs). Mitochondria play crucial roles in energy production and cellular signaling, but the key features of mitochondrial physiology and particularly of mitochondria-derived peptides (MDPs), remain underexplored in senescence responses. Here, we used primary human fibroblasts made senescent by replicative exhaustion, doxorubicin or hydrogen peroxide treatment, and examined the number of mitochondria and the levels of mitochondrial respiration, mitochondrial DNA methylation and the mitochondria-encoded peptides humanin, MOTS-c, SHLP2 and SHLP6. Senescent cells showed increased numbers of mitochondria and higher levels of mitochondrial respiration, variable changes in mitochondrial DNA methylation, and elevated levels of humanin and MOTS-c. Humanin and MOTS-c administration modestly increased mitochondrial respiration and selected components of the SASP in doxorubicin-induced senescent cells partially via JAK pathway. Targeting metabolism in senescence cells is an important strategy to reduce SASP production for eliminating the deleterious effects of senescence. These results provide insight into the role of MDPs in mitochondrial energetics and the production of SASP components by senescent cells.

Nrf2-dependent induction of innate host defense via heme oxygenase-1 inhibits Zika virus replication

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Hanxia; Falgout, Barry; Takeda, Kazuyo

We identified primary human monocyte-derived macrophages (MDM) as vulnerable target cells for Zika virus (ZIKV) infection. We demonstrate dramatic effects of hemin, the natural inducer of the heme catabolic enzyme heme oxygenase-1 (HO-1), in the reduction of ZIKV replication in vitro. Both LLC-MK2 monkey kidney cells and primary MDM exhibited hemin-induced HO-1 expression with major reductions of >90% in ZIKV replication, with little toxicity to infected cells. Silencing expression of HO-1 or its upstream regulatory gene, nuclear factor erythroid-related factor 2 (Nrf2), attenuated hemin-induced suppression of ZIKV infection, suggesting an important role for induction of these intracellular mediators in retardingmore » ZIKV replication. The inverse correlation between hemin-induced HO-1 levels and ZIKV replication provides a potentially useful therapeutic modality based on stimulation of an innate cellular response against Zika virus infection. - Highlights: •Hemin treatment protected monocyte-derived macrophages against Zika virus (ZIKV) infection. •Innate cellular protection against ZIKV infection correlated with Nrf2-dependent HO-1 expression. •Stimulation of innate cellular responses may provide a therapeutic strategy against ZIKV infection.« less

Two distinct cellular proteins interact with the EIa-responsive element of an adenovirus early promoter.

PubMed Central

Jansen-Durr, P; Wintzerith, M; Reimund, B; Hauss, C; Kédinger, C

1990-01-01

EIa-dependent transactivation of the adenovirus EIIa early (EIIaE) promoter is correlated with the activation of the cellular transcription factor E2F. In this study we identified a cellular protein, C alpha, that is distinct from E2F and that binds two sites in the EIIaE promoter, one of which overlaps with the proximal E2F binding site of the EIIaE promoter. The possible involvement of C alpha in the EIa responsiveness of this promoter is discussed. Images PMID:2139142

The Effect of Rituximab on Vaccine Responses in Patients with Immune Thrombocytopenia

PubMed Central

Nazi, Ishac; Kelton, John G.; Larché, Mark; Snider, Denis P.; Heddle, Nancy M.; Crowther, Mark A.; Cook, Richard J.; Tinmouth, Alan T.; Mangel, Joy; Arnold, Donald M.

2013-01-01

B-cell depletion therapy may impair vaccine responses and increase infection risk in patients with immune thrombocytopenia (ITP). Capitalizing on a multicenter randomized placebo-controlled trial, we investigated the effects of rituximab on the antibody and cellular responses to Streptococcus pneumoniae polysaccharide vaccine and Haemophilus influenzae type b (Hib) conjugate vaccine in ITP patients. Of 60 patients in the main trial, 24 patients received both vaccines 6 months after rituximab (n=17) or placebo (n=7). Among 20 evaluable patients, 3/14 (21%) in the rituximab group and 4/6 (67%) in the placebo group achieved a 4-fold increase in anti-pneumococcal antibodies (p=0.12). For anti-Hib antibodies, 4/14 (29%) and 5/6 (83%), respectively, achieved a 4-fold increase (p<0.05). Fewer patients in the rituximab group demonstrated functional Hib killing (2/14 [14%] versus 5/6 [83%], p<0.05). Three of 14 rituximab-treated patients failed to respond to vaccines by any criteria. After vaccinations, pre-plasma cell blasts and interferon-γ secreting T-cells were reduced in rituximab-treated patients. We found that antibody responses were impaired for at least 6 months after rituximab. Cellular immunity was reduced in parallel with the depleted B-cell pool. These findings have implications for the timing of vaccinations and the mechanism of infection after rituximab in patients with ITP. PMID:23851398

Impaired innate, humoral, and cellular immunity despite a take in smallpox vaccine recipients.

PubMed

Kennedy, Richard B; Poland, Gregory A; Ovsyannikova, Inna G; Oberg, Ann L; Asmann, Yan W; Grill, Diane E; Vierkant, Robert A; Jacobson, Robert M

2016-06-14

Smallpox vaccine is highly effective, inducing protective immunity to smallpox and diseases caused by related orthopoxviruses. Smallpox vaccine efficacy was historically defined by the appearance of a lesion or "take" at the vaccine site, which leaves behind a characteristic scar. Both the take and scar are readily recognizable and were used during the eradication effort to indicate successful vaccination and to categorize individuals as "protected." However, the development of a typical vaccine take may not equate to the successful development of a robust, protective immune response. In this report, we examined two large (>1000) cohorts of recipients of either Dryvax(®) or ACAM2000 using a testing and replication study design and identified subgroups of individuals who had documented vaccine takes, but who failed to develop robust neutralizing antibody titers. Examination of these individuals revealed that they had suboptimal cellular immune responses as well. Further testing indicated these low responders had a diminished innate antiviral gene expression pattern (IFNA1, CXCL10, CXCL11, OASL) upon in vitro stimulation with vaccinia virus, perhaps indicative of a dysregulated innate response. Our results suggest that poor activation of innate antiviral pathways may result in suboptimal immune responses to the smallpox vaccine. These genes and pathways may serve as suitable targets for adjuvants in new attenuated smallpox vaccines and/or effective antiviral therapy targets against poxvirus infections. Copyright © 2016 Elsevier Ltd. All rights reserved.

Nuclear translocation of Skp2 facilitates its destruction in response to TGFβ signaling

PubMed Central

Wu, George

2011-01-01

Skp2, a F-box protein that determines the substrate specificity for SCF ubiquitin ligase, has recently been demonstrated to be degraded by Cdh1/APC in response to TGFβ signaling. The TGFβ-induced Skp2 proteolysis results in the stabilization of p27 that is necessary to facilitate TGFβ cytostatic effect. Previous observation from immunocytochemistry indicates that Cdh1 principally localizes in the nucleus while Skp2 mainly localizes in the cytosol, which leaves us a puzzle on how Skp2 is recognized and then ubiquitylated by Cdh1/APC in response to TGFβ stimulation. Here, we report that Skp2 is rapidly translocated from the cytosol to the nucleus upon the cellular stimulation with TGFβ. Using a combinatorial approach of immunocytochemistry, biochemical-fraction-coupled immunoprecipitation, mutagenesis as well as protein degradation assay, we have demonstrated that the TGFβ-induced Skp2 nucleus translocation is critical for TGFβ cytostatic effect that allows physical interaction between Cdh1 and Skp2 and in turn facilitates the Skp2 ubquitylation by Cdh1/APC. Disruption of nuclear localization motifs on Skp2 stabilizes Skp2 in the presence of TGFβ signaling, which attenuates TGFβ-induced p27 accumulation and antagonizes TGFβ-induced growth inhibition. Our finding reveals a cellular mechanism that facilitates Skp2 ubiquitylation by Cdh1/APC in response to TGFβ. PMID:21212736

Impaired Innate, Humoral, and Cellular Immunity Despite a Take in Smallpox Vaccine Recipients

PubMed Central

Kennedy, Richard B.; Poland, Gregory A.; Ovsyannikova, Inna G.; Oberg, Ann L.; Asmann, Yan W.; Grill, Diane E.; Vierkant, Robert A.; Jacobson, Robert M.

2017-01-01

Smallpox vaccine is highly effective, inducing protective immunity to smallpox and diseases caused by related orthopoxviruses. Smallpox vaccine efficacy was historically defined by the appearance of a lesion or “take” at the vaccine site, which leaves behind a characteristic scar. Both the take and scar are readily recognizable and were used during the eradication effort to indicate successful vaccination and to categorize individuals as “protected.” However, the development of a typical vaccine take may not equate to the successful development of a robust, protective immune response. In this report, we examined two large (>1,000) cohorts of recipients of either Dryvax® or ACAM2000 using a testing and replication study design and identified subgroups of individuals who had documented vaccine takes, but who failed to develop robust neutralizing antibody titers. Examination of these individuals revealed that they had suboptimal cellular immune responses as well. Further testing indicated these low responders had a diminished innate antiviral gene expression pattern (IFNA1, CXCL10, CXCL11, OASL) upon in vitro stimulation with vaccinia virus, perhaps indicative of a dysregulated innate response. Our results suggest that poor activation of innate antiviral pathways may result in suboptimal immune responses to the smallpox vaccine. These genes and pathways may serve as suitable targets for adjuvants in new attenuated smallpox vaccines and/or effective antiviral therapy targets against poxvirus infections. PMID:27177944